Why did they need to fix the fights?
I didn't see any advantage to them to do this, and on top of that they said the fighters didn't even need to know it was fixed. What? They were so sure the guy who picked (fixed) the handicap would always lose? I doubt that anyone could be sure of that? So why did they need to fix it with the marble trick? Especially for the undercard where no one cares which fighter wins? Was it just another plot element thrown in to show how corrupt they were? The fighters don't even need to know? That's absurd, it's not fixed if they don't know.
In addition, one of the things fans like about this kind of fighting, UFC, MMA, full contact etc is that it's not fixed as boxing sometimes was and wrestling always is. So to make this film about this kind of fighting and then have promoters of the worst kind "fixing" the fight while dumb ass TV hosts don't know? Wow, that's a double insult, take a MMA hero and make him a chump because he can't see a fix right in front of him, that makes him look stupid, then overall, to imply that this sport is capable of, and likely, fixed is an insult to a sport that is not fixed.