The program I’m talking about has no such clause. I believe the solution would be for them to pay up past and present disputes and add a clause to the T&C’s to avoid future confusions.
I agree. To avoid breaking their current T&Cs, they should pay up, and then they should add a clause to their T&Cs indicating that they reserve the right to review situations like this in the future.
I wouldn’t like such a clause, and I would probably think twice about promoting a program that has a clause like this — but, the clause does need to be there for me to make an educated decision about whether to promote the program.
What would have happened if your player had simply cashed out? Would you be expected to repay the negative balance? At least he is playing it back — now the program will earn 65-70% of $X instead of 0% of $X.