There's no separate, unchallenged easily verifiable evidence that contradicts the claim that a Jewish Rabbi lead a mass movement of ecumenical reformists in the 1st century AD.

This is not necessary. For one, the burden of proof is on whomever makes the extraordinary claim, not whomever wishes to contradict or refute it. Second, no one is challenging the idea that there was a movement started sometime around then, somewhere around there. That is not an extraordinary claim - miracles and magic, however, are pretty extraordinary.

We have an abundance of accounts, many of them from the Roman scholars of the era, describing the movement and its members and their beliefs and activities.

No one is suggesting that Christianity doesn't exist. The claim is that miracles and magic were happening, and OP is challenging that claim.

Then we have a litany of Gospels, of which the nascent church had to scrub down precisely because so many of them were believed heretical a century later.

Why were some of these writings accepted and some weren't? Could it be because many of the rejected texts were contradictory, and thus - especially if taken with the canonized text - were ultimately unreliable at best, and outright fiction at worst? What was the methodology for determining which of them were true, and which weren't?

I'm a bit tired of hearing "Nothing exists" when what you're really saying is "I don't personal accept any of the testimony because I don't like the people saying it".

That is not at all what I'm saying, and I dare you to show me where I did

In this case, I'm not addressing Christians at all - I'm only concerned with the evidence, like OP. If the evidence that someone 2000 years ago was tossing around miracles and magic comes from a single, curated collection of scripts with dubious provenance that were hand-copied multiple times over centuries, translated & transliterated (many times inaccurately), with little additions and likely edits & deletions along the way, you're going to have to come up with something a little less biased to convince me. That's the whole point OP is making.