First, let me thank you for answering.
> That is, if the apostles fabricated the name or
> town[?] of Nazareth, why would they willingly
> die for what the knew to be a lie? This would
> seem to erode any logical comparison to present-
> day Muslims [for ex] who willingly die for what
> they BELIEVE to be true.
I'm not saying and I don't think Zindler thinks that the martyrs who were believers in the Gospels made up the lie about Nazareth, but just gullibly believed a lie. I'm suggesting the Gospel writers made it up, specifically the writers of the Gospels of Matthew and Luke (Mark, the first Gospel, evidently didn't mention Nazareth). I suspect that when they made up their history of Jesus they confused the idea that according to the Old Testament the Messiah should be of the Branch of Jesse (a descendant of King David) with the idea that he had to be from a place called the Branch = Nazareth. They made a similar mistake with his supposed Virgin birth. It's not clear that the writers of the Gospels were also the martyrs they were claimed to be.
Your Muslim example is very good. There are many other examples of people willing to die for a lie.
Your argument is invalid, however. Just because someone is willing to die for an idea does not prove the idea is true, although it's doubtful someone would willingly die for an idea they knew or should have known was false. This happens much more rarely in very deluded persons.
It's possible that Apostles Y and Z who knew or suspected the truth about Nazareth and the historicity of Jesus weren't willing to die for it. The Jesus they believed in and were willing to die for was spiritual only. Someone years later may have claimed that Apostles Y and Z were martyrs for ideas like the physical existence of Jesus, but maybe they weren't. It's similar to assuming the Jesus Saul/Paul believed in was the same one taught by the Gospels. Evidently, he believed in a spiritual Jesus, not the one from Nazareth. Jesus of Nazareth was invented after Paul.