Just looking at the hush money payments, he has the evidence to back it up.
So, one of a multi-billionaire's lawyers has a cancelled check signed by his client - someone who pays him, the lawyer, money.
That's some strong evidence of wrong-doing, there.
Although it doesn't, let's pretend the memo line of the check said, "to pay for the NDA with Stephanie Cliffords, aka, Stormy Daniels". Would there be anything illegal about that?
Well, if the check were written on the "Trump-Pence 2016" campaign fund, which it's not, it would. Since it's not, we have a multi-billionaire giving a check to his lawyer from his personal account which may or may not have been to pay for a completely legal transaction.
Whew, I bet Trump is shaking in his boots.