If the perpetrators move to a different country, then I don't expect a small island nation such as Curaçao to have the diplomatic influence to force the extradition. And in all probability, the Curaçao authorities don't care. The victims belong to various foreign nations, and as long as the locals are not conned, the authorities will remain cold to the investigation. The only precaution we can take is to limit our participation to gambling sites that have a good reputation. Don't get fooled by generous promotional offers from shady sites.
Did a bit of research and it seems like any dispute about the user and the casino is outside the jurisdiction of Curacao. It's not that it's ignored, but rather it's just straight up outside of their decision making, they just give you a license and talk about the money, but that's it.
However, if you face an issue with a casino that is a Curacao licensee, you cannot expect the gambling regulator to take a stance on the matter. You will have to resolve the situation on your own and get in touch with the casino management. If your attempts turn fruitless, you can submit the case to the Curacao Licensing Board. You also have to present the communication you had with casino’s officials and explain the reason why you think you have been unfairly treated.
You even have to go straight up to the higher-ups just to talk about it, kind of a pain in the ass so might as well just go for other casinos tbh. Plus, I don't think local authorities would even care, even if their citizens are scammed. The license only operates on countries that allows gambling and most scams are pretty much the own of ones self. Ofc, if it were to grow into a big case, then that's a different issue.