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.
Seems yes, maybe the user may set the table like this : exchange<=>Electrum<=>Mixer<=>Casino, vice versa
Better if it goes like this
exchange<=>Electrum<=>Mixer<=>Electrum<=>Casino
Because casinos also can freeze our account if it comes from mixing website due to AML policy.
Why we should do such complicated process just for gambling?
Above complicated process may cost some money and wont really worth for small amount of money.
Simply choose any exchanges that does not against gambling, this way we do not need to spend more money for several transactions.