This is most likely true, Stake/Primedice both the same scam operating under Curacuo License where is prohibited in their country. I am gonna file a lawsuit for all the money they've scammed me off.
If you are scammed, depending on where you live and how serious are institutions in your country, you can report them to authorities in your country and they will (at at least they should) request international legal assistance from Serbia.
You can also report them to Serbian
Ministry of Interior and
public prosecutor's office, but I believe that it would be better if you go through your countries institutions.
If you are serious about lawsuit, I'm not sure, but it's probably the best to wait for criminal conviction. And you will need to be patient, because litigation processes in Serbia are slow and can take years, so I'm not sure if it's worth it.
U losing money at stake is not a scam.
According to his previous posts, he is referring to some unpaid bonuses, not losing money.