This site points to far too many ancient sources for there to be any question about the 96 CE authorship of the book of Revelation.
The problem is there are not "too many ancient sources" there Is but one, Irenaeus. Eusebus, repeats what Irenaeus writes, and on it goes through the years from one writer to the next. Other than Irenaeus, no one heard what Polycarp said.
This is what Iranaeus wrote, that tells us When and under what conditions Irenaeus heard Polycarp speak about anything. In my opinion it is hardly conclusive evidence to base doctrine on.
"For while I was
still a boy I knew you in lower Asia in Polycarp's house when
you were a man of rank in the royal hall and endeavoring to stand well with him. I remember the events of those days more clearly than those which happened recently, for what we learn
as children grows up with the soul and is united to it, so that I can speak even of the place in which the blessed Polycarp sat and disputed, how he came in and went out, the character of his life, the appearance of his body, the discourses which he made to people, how he reported his intercourse with John and with the others who had seen the Lord, how
he remembered their words, and what were the things concerning the Lord which he had heard from them, and about their miracles, and about their teaching, and how
Polycarp had received them from the eyewitnesses of the word of life, and reported all things in agreement with the Scriptures. I
listened eagerly even then to these things through the mercy of God which was given me, and made notes of them,
not on paper but in my heart, and ever by the grace of God do I truly
ruminate on them, and I can bear witness before God that if that blessed and apostolic presbyter ....."
http://www.earlychristianwritings.com/text/irenaeus-eusebius.html
So what is the evidence that we do have. Irenaeus wrote, as an older, adult man about....
He was a child, listening to adult men discuss the scriptures. He said he wrote what he remembered Polycarp said on his heart. He himself was not old enough to take part in the discussions.
So was Irenaeus a student of Polycarp in the way most people would define a student? A child in a Sunday School class would be a student but what they heard would be geared to children's ears and they could take part in the discussion. So Irenaeus was not even a teenager at the time he heard Polycarp.
Could his memory have been mistaken about which ruler had sent John to the Isle of Patmos?
According to Eusebius (AD325), Irenaeus (130 - 202) said,
"We will not, however, incur the risk of pronouncing positively as to
the name of Antichrist; for if it were necessary
that his name should be distinctly
revealed in
this present time, it would have been announced by him who beheld the apocalyptic
vision. For
that was seen no very long time since, but almost in our day, towards the end of
Domitian's reign."
What was seen, the name of the Antichrist, the vision, John, the book of Revelation itself ? What is "not so long time toward the end of Domitian's reign"
In another place, which I can find if necessary, Irenaeus speaks of it as being in 'antiquities', so he must being speaking of two different 'its'.
Is it possible that the reason John was not martyred during Nero's reign, as Peter and Paul where and James also was murdered, is because he was on the Isle of Patmos? Is it possible that this is the way the Lord preserved his life during those years of persecution?
To make a solid doctrine on one man's word about something he heard as a child is not logical or prudent.