I just stumbled on this roulette as it looks fun to look at. So if the challenge is done by someone, he'd win $100 and at first thought of mine if it is really breakable and designed to at least be broken by certain amount player? Reading the thread, cmiiw, there have been 3 winners already.
I believe there were more winners in the past when it originally launched. The challenge itself isn't particularly difficult to complete as long as you have a lot of luck on your side.
And apart from that, you've got a bounty of $100 whoever finds some flaw on your roulette. Sounds good but if it's with these bugs and flaws, I'd increase the bounty because someone who might find a backdoor or hole might abuse that for more instead of reporting that with that amount of reward, just saying.
This is a small site with a small budget which is why I don't think op would increase the amount for the bounty unless absolutely necessary.