Metaspins shared the link to the LCB thread where your complaint was rejected and the mediator agreed with the casino's findings. Can you post the complaint links from the remaining sites?

I would advice you to focus on the matter at hand. What happens with US and Dutch players won't help your case. Curacao licenses restrict those countries and several others, like Germany, France, the UK, etc. It's your job and each player's job to thread the TOS and rules of the service you sign up for. 

I agree with you on this point. But, crypto casinos work differently from traditional fiat casinos that own licenses from strict regulators like the ones in Malta or the UK. Several years back I made Which casinos have IP blocks in place for restricted countries? The idea was exactly what you mentioned. I wanted to check if the casinos allow players to access and sign up using IPs from restricted countries. Some do, others don't. You can check the results in the thread.