Don't worry, no bookmaker or anyone else will ban you for changing dns to 1.1.1.1 or 8.8.8.8 (google dns) or whatever else. This method just helps to access sites if your ISP block them, it's not hiding your real IP in anyway. Just make sure they allow citizens of your country to play.
In my coutry goverment banned access to all foreigh gamblings sites, but its still legal to play everywhere so I’m fine.
Good luck on that I am skeptical about the whole system what if that against the rule of the site you are accessing and mind you if you hide your protocol Ip address and not use a VPN which server information will be on a third-party site which is the casino.
On second thought what if the account on the gambling has issues and you are asked to provide some information to get through most especially when there is a huge winning and you want to withdraw issues with KYC how do you resolve such problem.