casino asked for game provider audit after one normal blackjack cashout

Had a really straightforward blackjack session, mostly flat betting, nothing fancy with the play or bet sizes. Took the balance up a bit and decided to cash out, thinking this was as standard as it gets. Now the casino hits me up saying my withdrawal is delayed for a “game provider audit”. Never seen that before for plain blackjack, especially when I barely changed table or did anything close to bonus abuse.

I’ve always heard of KYC stuff or rare checks on slots after weird wins, but for a single blackjack cashout where the session was just normal play, it seems odd. My account is already fully verified and I used my own device and connection. Curious if anyone else has run into this “provider audit” excuse, or is this becoming a new thing to watch out for even with table games? If it keeps up for blackjack grinders, it’s going to make playing there feel pretty pointless.