Since this is a cash game, the rules that apply are those of your Gaming Agency and the House, the TDA has no rules for cash games. Robert's Rules of Poker, V. 11 says the following:
5. A ruling may be made regarding a pot if it has been requested before the next deal starts (or before the game either ends or changes to another table). Otherwise, the result of a deal must stand. The first riffle of the shuffle marks the start for a deal.
6. If a pot has been incorrectly awarded and mingled with chips that were not in the pot, and the time limit for a ruling request given in the previous rule has been observed, management may determine how much was in the pot by reconstructing the betting, and then transfer that amount to the proper player.
Based on the above, I would suggest that from the House standpoint, the pot has to stand as paid. That said, there is NOTHING against these two players, assuming one of them was awarded the incorrect pot, coming to a settlement between themselves.
Chet