There's nothing to debunk. That's the entire point. He's trying to prop up his claims with more claims. If we cannot determine the veracity of his anecdotes, they are of no use to us in determining the validity of his conclusions.

His entire response could be boiled down to "Trust me, bro".

I get the feeling he knows he cannot defend his position based on either commonly known information or on reasoning about the situation. So he has to purport to have special information that most don't. And that special information, which you cannot have, is enough to turn everything around. But he also won't give you enough information to independently verify. He won't tell you which campaigns he did these things for, which politicians he worked for. But they were top men. Top. Men.