Mirror link is intended to solve all the issue for different type of restriction set by the country ISP provider while they allow such country as per their license coverage. Doing some tweaking on DNS or VPN is always a bad idea since it might result to problem in case you forgot this setup when you enter on different casino that has restrictions on your country.
You are correct about the mirror link. I recently came across a thread on the gambling board discussing a new casino. Users from a non-restricted country are having trouble accessing the platform. What's odd is that the promotion of the casino is being handled by someone who lives in Bangladesh. I assume that some casinos don't conduct proper research and end up collaborating with the wrong individuals. It would have been great if they had hired icopress, as he is known for having the best marketing skills for promoting a crypto casino in the forum.