Forget "Anderson Silva" money, that is more than Tyson money. That would be the biggest guarantee in the history of combat sports. The UFC would need to sell about double the amount of their best ppv numbers to break even for that fight.
As they say in boxing, if you price yourself out of the fight, it means you aren't interested in the fight.
I, however, wouldn't be surprised to see the fertita's privately (and secretly) finance it for their own eccentric curiosity.