I'm pretty sure pay would have been same as usual for both women, with a 500 dollar bonus for winner.
I agree that a bigger gap in pay like 80 20 in favour on winner would lead to very intense catfights, but then again, I feel less women would even agree to fight in first place if this was the deal.
The fan bonus that was mentioned on twitter could definitely hype both women up, knowing that winner will be getting extra bonus money into their cash app account etc.