Judge Judy is not a real judge. lol. Her legal authority is based on contract that the "parties" sign saying that they agree to give up any legal rights they have in the case and do whatever Judge Judy tells them they have to do.
Much like in other contracts, if Judge Judy makes a ruling that is inconscionable, the contract is voided and the parties don't need to abide. However, any ruling that gives adequate consideration to both parties must be abided...
To be clear...Judge Judy is NOT part of the legal system. Therefore, it makes no sense to compare her contract arbitrations to an actual court case like the GSEs.