From Silent Lambs web site I obtain the following quotes from letters to Bodies of Elders and Statements made by JR Brown, Public Affairs Office and Mario Mareno , Legal Affaires Department. ( bold and caps added for emphasis)

Those who have confessed to child molestation, or who have been found guilty of child molestation by the congregation on the basis of two or more CREDIBLE witnesses, should appear on the Child Protection List........

There are, however, many other situations that are connected with the abuse of a child. For example, there may be just one eyewitness, and the brother denies the allegation.......

Where the principle in 1 Timothy 5:19 cannot be satisfied enter "none" in the "Congregation Action" column.........

The following are public relation statements of J R Brown, Public Affairs Office, WTBTS

f there is sufficient evidence that someone has exploited children in this way, he may be disfellowshipped (excommunicated). A sincerely repentant former child molester may be allowed to remain a member of the faith , .......

Brown said the faith does require at least two witnesses to prove any kind of wrongdoing -- including child molestation -- because that is what is taught in the Bible. But corroborating evidence can be used instead of a second witness to prove wrongdoing,.......

A known child molester does not qualify for appointment as a. church elder or for any other position of responsibility in any congregation of Jehovah's Witnesses.
JR Brown........

What conclusions can be draw from these statements?

1.....The criteria for establishing guilt of a child molester is a self-confession or two or more credible witnesses, the word credible implies that it be an adult person who is an eyewitness. A child may not be considered as credible; he may be providing false inculcated memories for example.
2..... No action is taken or recorded if two witnesses are not available, according to lTim 5:19 .
3..... Sufficient evidence means there must be two credible witnesses or a confession as above.
4.....A known child molester, means the child molester is known publicly through the courts or publicity, within or outside the congregation. This knowledge is not revealed by the elders, they guard their confidentiality.
5.....A child molester could confess his wrongdoing to the elders, showing sincere genuine repentance and remain in good standing in the congregation.

From the statements made to date about pedophilia by the WT what can we infer about their strategy ? I believe that they will defend themselves with a freedom of religion stance. The Bible calls for TWO WITNESSES and if the wrongdoer is repentant he can remain a member of the faith.

Mario Moreno is reported as saying:

We go by what we believe the Bible says, and we don't change for anybody." If Caesar has a law, and it does not conflict with God's law, we follow it."

My question is: IS THERE REFERENCES IN THE BIBLE WHERE GUILT IS ESTABLISHED WITHOUT TWO WITNESSES?

Yes there are several references where secret wrongdoings are done and the Bible gives instructions on how to handle them.

The WT uses 1 Tim 5 ;19 as a basis of their belief for handling wrongdoing, especially if elders are involved. The text says: (all texts quoted from NASB)

1Ti 5:19 Do not receive an accusation against an elder except on the basis of two or three witnesses.

Commentators on this text, state that Paul, in view of the fact that elders are in positions of authority , they are subject for attacks from many directions, just as politicians are often attacked by opposers . He is telling Timothy to refer to the provisions of the Law of Israel, to lay to rest any accusations.

The second part of the text is not emphasized by WT writers.

1Ti 5:20 Those who continue in sin, rebuke in the presence of all, so that the rest also will be fearful of sinning.
If an elder denies or persists in sin then they are to receive public rebuke in the presence of all.

Deu 19:15 "A single witness shall not rise up against a man on account of any iniquity or any sin which he has committed; on the evidence of two or three witnesses a matter shall be confirmed.

The WT usually ends the quotation at this point and base their decisions only if the evidence of two witnesses is produced. But what if it is a wrongdoing done in secret, such as adultery or child molestation and the guilty party denies it? They usually say, to the victim, sorry, no two witnesses, you have no evidence, you will just have to shut up about it and if you don't then you will be guilty of slander and bring reproach on Jah's holy organization.

What does the continued reading of the passage say?

Deu 19:16 "If a malicious witness rises up against a man to accuse him of wrongdoing ,
Deu 19:17 then both the men who have the dispute shall stand before the LORD, before the priests and the judges who will be in office in those days.
Deu 19:18 "The judges shall investigate thoroughly, and if the witness is a false witness and he has accused his brother falsely ,
Deu 19:19 then you shall do to him just as he had intended to do to his brother. Thus you shall purge the evil from among you.
Deu 19:20 "The rest will hear and be afraid , and will never again do such an evil thing among you.
Deu 19:21 "Thus you shall not show pity: life for life, eye for eye, tooth for tooth, hand for hand, foot for foot.

If a child is a victim of molestation, and brings the crime before the elders and the molester denies it, one of them is a false witness, it could be either one. The alleged victim accuses his opponent with, you molested me. . The alleged perpetrator responds, you are a liar. What instructions are the judges to follow? They must investigate the matter thoroughly. In our day, this could mean, doctors statements, dna samples, alibis, counselers , body language, the victim’s state of mind, and many other things. Who is qualified to carry out such thorough investigations? Need I ask?

A second reference of secret sin is in Numbers. I will quote the entire passage for facility of reading it here by not stopping to look it up and also to show the context.

Num 5:11 Then the LORD spoke to Moses, saying,
Num 5:12 "Speak to the sons of Israel and say to them, 'If any man's wife goes astray and is unfaithful to him,
Num 5:13 and a man has intercourse with her and it is hidden from the eyes of her husband and she is undetected, although she has defiled herself, and there is no witness against her and she has not been caught in the act,
Num 5:14 if a spirit of jealousy comes over him and he is jealous of his wife when she has defiled herself, or if a spirit of jealousy comes over him and he is jealous of his wife when she has not defiled herself,
Num 5:15 the man shall then bring his wife to the priest, and shall bring as an offering for her one-tenth of an ephah of barley meal; he shall not pour oil on it nor put frankincense on it, for it is a grain offering of jealousy, a grain offering of memorial, a reminder of iniquity.
Num 5:16 'Then the priest shall bring her near and have her stand before the LORD ,
Num 5:17 and the priest shall take holy water in an earthenware vessel; and he shall take some of the dust that is on the floor of the tabernacle and put it into the water.
Num 5:18 'The priest shall then have the woman stand before the LORD and let the hair of the woman's head go loose , and place the grain offering of memorial in her hands, which is the grain offering of jealousy, and in the hand of the priest is to be the water of bitterness that brings a curse.
Num 5:19 ' The priest shall have her take an oath and shall say to the woman, "If no man has lain with you and if you have not gone astray into uncleanness , being under the authority of your husband, be immune to this water of bitterness that brings a curse;
Num 5:20 if you, however, have gone astray, being under the authority of your husband, and if you have defiled yourself and a man other than your husband has had intercourse with you"
Num 5:21 then the priest shall have the woman swear with the oath of the curse, and the priest shall say to the woman ), "the LORD make you a curse and an oath among your people by the LORD'S making your thigh waste away and your abdomen swell;
Num 5:22 and this water that brings a curse shall go into your stomach, and make your abdomen swell and your thigh waste away." And he woman shall say, "Amen. Amen."
Num 5:23 'The priest shall then write these curses on a scroll, and he shall wash them off into the water of bitterness.
Num 5:24 'Then he shall make the woman drink the water of bitterness that brings a curse, so that the water which brings a curse will go into her and cause bitterness.
Num 5:25 'The priest shall take the grain offering of jealousy from the woman's hand, and he shall wave the grain offering before the LORD and bring it to the altar ;
Num 5:26 and the priest shall take a handful of the grain offering as its memorial offering and offer it up in smoke on the altar, and afterward he shall make the woman drink the water.
Num 5:27 'When he has made her drink the water, then it shall come about, if she has defiled herself and has been unfaithful to her husband, that the water which brings a curse will go into her and cause bitterness, and her abdomen will swell and her thigh will waste away, and the woman will become a curse among her people .
Num 5:28 'But if the woman has not defiled herself and is clean, she will then be free and conceive children.
Num 5:29 'This is the law of jealousy: when a wife, being under the authority of her husband, goes astray and defiles herself ,
Num 5:30 or when a spirit of jealousy comes over a man and he is jealous of his wife, he shall then make the woman stand before the LORD, and the priest shall apply all this law to her.
Num 5:31 'Moreover, the man will be free from guilt, but that woman shall bear her guilt.'

Is this procedure Theocratic Voodoo? Call it that if you wish. Each point in this account has significance. For the sake of brevity, I refrain from making further points, and let the text stand on its own. The woman was swearing an oath, just as in court today, you swear to tell the truth on the Bible, so help you God. Excuse my vocabulary, but she was laying her ass on the line just as some rape victims in modern times, are willing to expose their reputations, honour and well-being before the courts to see that justice is done. My point here is , do elders today, in a situation where concealed wrongdoing is in question, are the disputants asked to swear, by Jehovah, by their organization, by the Bible or on whatever they hold sacred that they are telling the truth?

Mat 26:59 Now the chief priests and the whole Council kept trying to obtain false testimony against Jesus, so that they might put Him to death.
Mat 26:60 They did not find any, even though many false witnesses came forward. But later on two came forward ,
Mat 26:61 and said, "This man stated, 'I am able to destroy the temple of God and to rebuild it in three days.' "
Mat 26:62 The high priest stood up and said to Him, "Do You not answer ? What is it that these men are testifying against You ?"
Mat 26:63 But Jesus kept silent. And the high priest said to Him, "I adjure You by the living God, that You tell us whether You are the Christ, the Son of God."
Mat 26:64 Jesus said to him, "You have said it yourself; nevertheless I tell you, hereafter you will see THE SON OF MAN SITTING AT THE RIGHT HAND OF POWER, and COMING ON THE CLOUDS OF HEAVEN."
Mat 26:65 Then the high priest tore his robes and said, "He has blasphemed ! What further need do we have of witnesses ? Behold, you have now heard the blasphemy;
Mat 26:66 what do you think ?" They answered, "He deserves death !"

Mark in his account about the witnesses who testified:
Mar 14:59 Not even in this respect was their testimony consistent.

The high priest did not have two witnesses that gave consistent evidence. So he demanded an oath from Jesus, I adjure you by the living God, that You tell us whether You are the Christ, the Son of God."

Jesus reply implies that the high priest, by asking the question, was the one bringing up the subject that Jesus was Christ. Jesus’ answer said he was the son of man, that comes with power and that power would come from heaven not from man.

Here then is another judicial hearing where there was not two witnesses and high priest resorts to requiring an oath to determine the charges.

The Bible is not silent on concealed sins, wrongdoings where there is no two eyewitnesses.

Job says:

Job 24:15 "The eye of the adulterer waits for the twilight, Saying, 'No eye will see me.' And he disguises his face.
Job 24:16 "In the dark they dig into houses, They shut themselves up by day; They do not know the light.
Job 24:17 "For the morning is the same to him as thick darkness, For he is familiar with the terrors of thick darkness

For the wrongdoer who thinks his sin is hidden in darkness, daylight comes and will reveal his sins and so he hates the light, it brings him trouble, shame and fear. Instead of the joy of morning, it is the darkness of mourning.

So Watchtower and all your people, Daylight comes. The Scriptures entreat you, Kiss the Son, before his daylight catches you with your pants down .