Yes, you're probably right about the backfire. It's better to look for another activity and accept the loss. Unfortunately, this will become more and more common, with people jumping on the opportunity to make easy money off those who are barely interested in soft power other than using it to get a visa. These people will never show up and will never even realize they got scammed. 😅
I'm not surprised. Plenty of people use Muay Thai as an excuse but never show up to their lessons, which gives ideas to scammers and questionable gyms. There will be more and more abuses from both sides until a proper cleanup happens. And sadly for you, you're genuinely interested in Muay Thai and face the results of it...