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.
in table tennis, after a score of 9-9, this casino blocks bets, and opens with a tie (10-10/11-11/12-12)
that is, after the score became 10-10, I immediately clicked on the redemption of the bet. there was plenty of time for the casino to issue a ransom before the score was 10-11 (at this score, the bets are closed again).
because I have done it many times before.
but today it turned out like this, and the casino did not go forward BECAUSE OF THEIR LAGS. That's what I want to convey to people.
Well, you must understand that anything built by humans Is not perfect, like you said that this is something you've been doing before with out any problem, I still believe there was no lag, in my personal understand of how stake's cashout bet operates, the 7 seconds is a Mandatory time the gambler must wait for the casino game provider to process the cashout, and this comes with some level of risk as you would have to make sure that in those 7 seconds, nothing changes in scores, else the cashout will be declined.
The reason you experienced this today might be because you weren't lucky enough today, probably the game score changed before the 7 seconds timer elapsed, this is also a possible reason, and not necessarily because the casino lag.
Do not think I am siding stake please, I am just trying to look at all the angles to how your issue could be possible and not necessarily stakes fault, I stand to be corrected in any part I made a mistake or misunderstood anything.