They already admitted their mistake what more do you want out of the issue? Every other casino i've tried makes mistakes from time to time as well.
Their self exclusion might not be perfect but as what the others mentioned there's usually an unsubscribe button for this type of stuff, you could've easily fixed the issue on your own.
because you just don't unsubscribe so you don't receive their emails and you can also block their emails and that's a problem solved, it sounds to me like you're trying to take this error to the extreme when it doesn't need to. Are you sure you are cured of the addiction?
I agree, it felt like OP wanted to get more out of that small mistake.