Can anyone tell me how will centralized know that the funds came from a gambling site? I'm only seeing threads before that someone claimed their account got frozen because funds came from a gambling site but no proof that the site itself tells their users that's the exact reason. Coinbase for example but not seeing cases like that in Binance. I think there is another reason why their account got frozen and not because the money was coming from a gambling site.
Furthermore, if OP is really worried, then an extra step of using a non-custodial wallet is necessary.
If funds came from any gambling site then there might have mentioned the sites name as several exchanges name also shown. If few sites, or few times it cant show the name of the site then there is a probable number of the wallets of a gambling site they may count.It might be something like the provided image below:

Exchanges and gambling sites will report their customer information to IRS that is why most casinos and exchanges which accepts people from US has mandatory KYC policy. OP can simply use an electrum wallet but even if he uses exchange<=>Electrum<=>Casino still the exchanges will find the transaction based on tracking and will freeze the account especially the coinbase.