I believe your problem emanated from the fact that you didn't read stakes casino rules.
I personally do not believe this to be a bug, you said that while the casino was still counting down on 7 seconds cash out limit, the score for the game you bet on changed from 10:10 to 10:11, now, you didn't tell us if this change was in your favor or against you. If the change was against you, I think it's normal that cash out would be declined by the game provider.
Responsibility goes both ways. If the bug or whatever you might consider it did play out against his favor, he would have had a right to nullify the losses and get his bet money back.
If a casino denies you your rights (which serious casinos would never do without a good reason) to taking advantage of a bug that sounds only fair to me. Technically anyone using the bug for personal gain could be seen as a hacker/thief.
I do not know why people like to switch the victim and perpetrator roles here.