This is how I imagine Rudy's salty pretzel logic nutshell-explanation to go:
The Ghoul: Our election fraud claims are truly truth.
The Press: What proof do you have that they're true?
The Ghoul: We haven't been able to provide proof as of yet because there's a conspiracy working against us to keep us from proving them true.
But really, why else would they be claiming there is no evidence if it all wasn't really true?
The Press: What proof do you have for such conspiracy?
The Ghoul: We don't yet have such evidence because of a conspiracy keeping us from proving the conspiracy.
The Press: Wait... so, essentially you're claiming that your election fraud claims are true... because you can't prove them to be true?
The Ghoul: That's the ticket.