They are most probably all made up by Thompson's fertile, delusional brain; or what's left of it. As to the WHYS of why he does it, that's up for grabs.
I agree it appears most likely Thompson is making it up himself. So moving on to the question of motive, I'm thinking we should check into who his editor is. It seems to me that if Thompson only does this once or twice, it could be he's a "lone nut" who is venting a personal political grudge, or gets his kicks from hoodwinking the public, or something like that. But if he keeps doing it repeatedly, as appears the case--we've now found at least three examples, I'd be willing to bet there's more out there--I start to wonder why his editor's letting him get away with it.