There are people saying all the Jews were still alive in Germany. For a matter of fact, I've recently been to a jewish restaurant. The owners seemed fine.
And those people are cranks because we have tons of evidence of the holocaust.
Conversely, in this case, Adrian Zenz is a crank because for a decade he's been unable to put up any. In an era where every single person carries a high def video camera in their pocket. It's a faith-based accusation.