Oh let's do this.

Paul never saw anything he admits as much. He claims to have met James who claims to be in the brotherhood of Christ, from the Greek word christus or annoited ones.

Josphius has two passages of interest. The first one is a known forgery. It has him expressing Trinity ideas that didn't exist at the time, it doesn't fit in the context of the page, is not in his writing style, and doesn't get mentioned to almost 3 centuries after publication. The second mention is also a very likely a forgery. If you read the entire section you can see that Josphius was talking about two different people one happened to be named James and the other happened to be named Jesus. It doesn't fit the chronology (James would be like 70 years old) and it doesnt fit the culture since it would require James to be an orthodox pharisse. Meanwhile the same exact words used to describe him are the same used by Matthew.

The Gospels are even worse. John copied from Luke, Luke from Matthew, and Matthew from Mark, and Mark from Paul. A copy of a copy of a copy of a copy of a copy. Each writer pushing their own agenda and willing to lie get it. There is maybe 4 or so sentences in Mark alone that can't be traced back to the OT, Paul, and popular Greek literature of the time. The supposed oral tradition could fit on a single page. Even that is questionable since ~99% of Greek writings are lost to us we don't know if the supposed oral tradition was part of that.

Nice attempt to sneak in an argument from authority with an argument ad populism. Now if you got any good evidence let me know. The simplest explaination of the data we have is that James was running a mystery cult and Paul took it seriously. Jesus is as historical as Batman.