How did they doubt him, like in what sense? Do some historical texts mention this more closely??
Here is a discussion at Livius:
https://www.livius.org/articles/legion/legio-xiiii-gemina/
In January 69, the civil war of the four emperors broke out when the governor of Germania Inferior, Vitellius, revolted. Galba panicked, was lynched and succeeded by Otho. The legions now had to choose and XIV, like the other legions of the Balkans, preferred Otho. Unfortunately, the legion did not arrive in time for the first battle of Cremona; a subunit fought for its emperor, but was defeated with the other Othonian legions. Vitellius, however, was merciful and sent the Fourteenth back to Britain. In the second round of the civil war, Vitellius versus Vespasian (the commander of the Judaean expeditionary force), XIV Gemina remained aloof.
What are some other parallels with John?
Joe didn't really find much in GJohn that's specific to events in Domitian's life. A good place to look would be the various references to the Holy Spirit. Regarding Domitian and the Holy Spirit, Joe said:
Although the ‘Holy Spirit’ is mentioned many times in the three synoptic Gospels and also in the Old Testament, it is typically referred to as an aspect of divinity that descends and fills a righteous person with godliness at important moments. ... There was no concept that the ‘Holy Spirit’ was a third distinct entity within the godhead.
The dualist concept of deity was consistent with the views of the Roman imperial cult, and it was consistent with the initial formulation of Flavian Christianity. There was no need to include Domitian in the system, because he had not been on the Judean battlefield like Vespasian (‘God the father’) and Titus (‘son of God’). To correct this slight to his ‘divinity’, Domitian promoted the ‘Holy Spirit’ to become a fully co-equal partnership with the Father and the Son.
A clearly Trinitarian formulation only occurs in the synoptic Gospels in Matthew 28:19, “Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit”, which many scholars believe was a late interpolation. In a few other passages in the synoptic Gospels, Jesus refers to the ‘Holy Spirit’ as a distinct entity from the ‘Son of Man’, but the use of this latter term is arguably enigmatic. The view of the ‘Holy Spirit’ as an equal member of the Trinity becomes clearer in the Gospel of John, and is fully developed in Revelation and the epistles of Paul. It is interesting to note that the ‘Spirit’ (that is, Pneuma) was also a technical term of the Imperial Cult that was used to describe the spirit of the emperor that existed within his statues (Paul Corby Finney, The Invisible God: The Earliest Christians on Art, p. 73).
As further evidence that GJohn was written together with Acts and Revelation, Joe gave this:
Another example of Domitian’s typology is a puzzle concerning the number three. To create the puzzle, the author used blocks of text from Josephus, Acts, and the Gospel of John, which were linked by rare triangle numbers. These numbers are: the 153 large fish in John 21:11, the 120 people in the congregation in Acts 1:15, the 276 people on Paul's ship in Acts 27:38, and the number of the beast, which is 666 (Revelation 13:18). The nth triangle number may be defined as the number of dots composing an equilateral triangle with n dots on a side, including the dots filling the interior of the triangle on a triangular grid. [......]
Acts describes Paul’s shipwreck in great detail and it is easy to see that its shipwreck story was somehow dependent to Josephus’s in that some of the parallel concepts occur in the same sequence - i.e. Felix, priests being imprisoned and sent to Caesar for judgment, the ship sinks or runs aground in the Adriatic Sea, the heroes (Josephus or Paul) act with courage and provide leadership, all passengers presumably survive, and then on to Puteoli. Thus, by way of the common link with Josephus’s Life, the passage in Acts 27 describing the shipwreck and containing the triangle number 276 is paired with the passage in Acts 1 containing the triangle number 120. (Of course, Acts 1 and Acts 27 are also paired simply because they both contain rare triangle numbers.)
However, the shipwreck story in Acts also contains many parallels to the ‘coming ashore’ story in John 21 featuring the triangle number 153.
[....] the ratio of 265:153 represents a good approximation of the square root of three. The ratio is physically represented as lines drawn on two circles to form a fish in a shape known as the Vesica Piscis, a term that literally means the "bladder of a fish". The Vesica Piscis is the intersection of two circles with the same radius with the center of each circle lying on the circumference of the other. The Vesica Piscis has been used since antiquity to create the fish shape that represents Christianity.
[....] while ‘Mathias’ (that is, a type of Josephus) was ‘numbered with the eleven’ in the ‘120’ story, we find the Centurion (that is, another type of Josephus) ordered the prisoners to swim to shore in the ‘276’ story, thus ‘subtracting’ the 11 prisoners from the 276 on the boat thereby leaving 265 still on the water. This creates the other half of the Vesica Piscis ratio 265/153.
This solution neatly ties together the references to ’Mathias’ and the ‘eleven’ from Acts 1:15-26, the references to prisoners, the centurion and ‘276’ in Acts 27, and the reference to 153 ‘fish’ in John 21. Furthermore, without the information relating to Josephus from his autobiography, and the realization that ‘Mathias’ and ‘Julius the centurion’ are both types of Josephus, the puzzle cannot truly be ‘solved’: there is no other justification for subtracting the eleven from the 276.
"Shakespeare's Secret Messiah" contains an entire chapter on Rabbinical Judaism and the Talmud. Here's the summary:
After learning that the Flavians had invented Christianity, I became curious as to why they provided the Rabbis with a land grant to establish Rabbinical Judaism. It seemed logical to me that as the Flavians had created one of the two religions that had replaced the militaristic form of Judaism, they also created the other.
I began an analysis of the literature of Rabbinical Judaism to determine if it contained clues, like those within the Christian canon, indicating that the Flavians had created that religion. This study led to the following conclusions:
1) Rabbinical Judaism was, like Christianity, a religion created by the Flavians.
2) Many of the original ‘Rabbis’ of the religion were not Jews, but Roman ‘converts’ or proselytes to Judaism, who were under the employment of the Flavians.
3) Much of the canon of the religion was not created for a theological purpose, but to mind-shape Judaism’s religious warriors into docile students obsessed with legal minutia.
4) Exactly as they had done with the Gospels, the Flavians constructed a satirical message within the religion’s canon to notify posterity that they had created Rabbinical Judaism and that the ‘God’ the Jews worshiped was the Flavian Caesar.
5) Rome was successful in both destroying the real Judaism, which was the xenophobic religion of the Maccabees, and, incredibly, in hiding this fact from history.
But, the specific parallels that Joe was able to identify within the Talmud were entirely related to Vespasian and Titus. He didn't find anything specifically about Domitian.
This looks pretty interesting.
We really need to get you a copy of the book. Did you have any luck reaching Joe at his email?