I can find no reference to Domitian's nickname. I would highly question his nickname as Nero since 1) Domitian preceded Nero and I would suspect wanted to forge his own legacy, and 2) Nero forced his wife to commit suicide. I doubt that #2 reason would endear Nero to him (but then again...).
That not withstanding, the reference posted above does far more than give a reference to a particular emperor. The Muratorian Canon states "…for the blessed apostle Paul himself, following the order of his predecessor John, he wrote to only seven churches by name, in the following order". As the text states, Paul followed John's order. This is rather difficult to refute if it is indeed true. Couple that with the Syrian text and Jerome's explanation, it makes a rather compelling argument that Revelation was written before 70AD. Given the fact that all we have is one little reference from Ignaeteus, the Syrian, Muratorian, and Jerome carries a bit more weight.
"Next Elliott reviews the early works which placed the writing of Revelation during Nero's reign or earlier. He finds these works to be of questionable value.
"Nor can it be wondered at: seeing that as to any contrary statement on the point in question, there appears to have been none whatsoever until the time of Epiphanius, Bishop of Salamis in Cyprus, in the latter half of the fourth century: ...whose chief work, On Heresies, is decried ... as 'full of blots and errors, through the levity and ignorance of the author:' ...For he speaks of St. John having prophesied when in the isle of Patmos, in the days of the Emperor Claudius: --a time when... it does not appear from history that there was any imperial persecution of the Christian body whatsoever..." (vol. I, p. 37)
" ...another testimony to the early date of the Apocalypse. The subscription to a Syriac version of the book, written about the beginning of the sixth century, is thus worded; 'The Revelation which was made by God to John the Evangelist in the island of Patmos, whither he was banished by the Emperor Nero.' But of what value is this opinion, then first broached, as it would appear?" ( vol. I, p. 38-39)
"Elliott adds this footnote which explains that Domitian was sometimes given the title of Nero.
"May not the mistake have arisen from Domitian having sometimes the title of Nero given him; and in fact the original writer of the Syriac subscription have meant Domitian, not Nero?" He includes in this footnote further proofs given in Latin of this title applying to Domitian. (vol. I pg. 39, footnote 1)"