Bug bounty hunting is not like this It should be a "bug" and actually affect a lot of things, sure you can get something in return for this but it shouldn't be too much, like maybe 20 bucks for something this simple.

The idea of a bug bounty where casinos pay as much as 1 bitcoin for people who can find it would be the bugs that could affect the casino very badly, like maybe a loophole that allows you to see the results beforehand type of big deal, not something like "max bet doesn't show on mobile" that is just a small design thing and doesn't really change much in the casino part of the deal. I am not saying don't give anything, you could totally give him something but it is not like he figured out there was a way to get everyone's password or anything, it was just a design problem.