Other precedents can point in the other direction. If a bank mistakenly puts $100,000 into your checking account, you are NOT allowed to keep it and have no valid claim to that money. It must be returned to the proper person/organization.
And in a situation closer to the internal PAC dispute, it appears that the PAC was overpaid various media/TV monies (I think it was about $50,000,000) and is going to be repaying that amount (to FOX???). The same thing could happen to USC/UCLA-they were paid money that according to the conference bylaws they had no right to, and therefore they would be obligated to repay those funds to the conference.
Just remember, I am not an attorney either, and did not spend the night at a Holiday Inn Express. I DID get a good night's sleep on my waterbed though.
