Well I do think he's being paid. Definitely. He wouldn't just rock over there to play an exhibition game in his own spare time. The regime probably contacted him as he is a bit of a loose cannon, plus there is no way anyone with any current relevance or credibility would agree to go over there.
You made the point that Rodman was doing it to remain relevant but it would take an awful lot more than that to remain relevant. If anything, he's ostracized himself from the American public even more by giving ridiculous statements about Kim jong Un being a friend for life.
I'd say Rodman is feeling the love for North Korea right now as its just stuck a couple of hundred thousand in his bank account.