You sure about that that? Vadim himself has admitted that financially the UFC deal (just before he signed for Affliction) was the best.
That is kind of true but also not fully accurate, the ufc would give him a contract that would pay more per fight than any other org, however if he has an open contract say dream wanted him to fight barnett on the nye card they might offfer him more money than he would earn for a single ufc event but if he was in the ufc he would be locked down to just the one org.