exchange<=>Electrum<=>Mixer<=>Electrum<=>Casino
Because casinos also can freeze our account if it comes from mixing website due to AML policy.
Not questioning your way but are you guys really serious that mixer should also be included in the process.
Just take your betting simple and easy. Use an exchange that doesn't have terms on gambling like Binance. They won't freeze your account because of gambling. If there's a change of policy they will make an announcement about it. If still worried, then take some extra steps by using Electrum. No need for any mixing service. It's too much for a step on me especially if you are just an average gambler.
You no need to do all such process when you are ready to give your tracking records and paid taxes even for your gambling rewards.