Assuming this May event takes place in Nevada, the fighter purses are public record and the truth will be known. Current top pay w/ a win is somewhere around what $225,000? Royce's payday?????
my uneducated guess, knowing Royce's dislike for current UFC rules/judging:
really doubt there's a win bonus for the fight as Royce wouldn't want to leave that up to the judges. But I guess there could be a win bonus for promotional reasons - if Zuffa wants to call it the biggest purse in UFC history or something (I doubt it, but you never know).