Building on some of the other ideas here, maybe you can introduce gamification concepts to help provide another possible solution to someone struggling with a gambling issue - as part of a suite of options. Gambling can often be a problem for the people who can least afford it. As suggested above, maybe it can also be used to reach goals, etc.
There could be a real opportunity here for trialling all sorts of new or different approaches. So, something like… “Hey, instead of using this money for XYZ, we’ll put it as a bonus interest amount on your savings account next month”.
Yes, people can get money from elsewhere and yes, they can do what they want with their money, but people are not always rational (even though we’d like to think we are) and it’s always worth trying new approaches for difficult problems.
Perhaps by approaching the issue in new or unexpected ways, Xinja might have some success.