Aside from the privacy I don’t really know what vpn helps you with. Most people that use VPN to access gambling site: which is not advisable ( since you’re sharing ip addresses with several other users that might be connected to that same server).
The only way I see VPN protecting cheaters is still related to privacy since the cheaters can create multiple accounts (for casinos that are against having multiple accounts) and then use VPN to access each of them -making your ip addresses different, that’s the only cheater protection I can think of right now, but the casino system will still be able to detect if the ip keeps on changing they might request for additional verification despite them allowing vpn just to be sure that they aren’t dealing with a cheater.
Maybe you've heard about such a service as browser anti-detection and even system-wide anti-detection? This software is quite expensive, as it allows you to randomize system and browser settings. It is in great demand among cheaters. You are right that many cheaters who use VPNs use them for multi-accounts. Cheaters regularly register on gaming sites by changing their IPs, thereby posing as if they are different people. But by changing only IP addresses, it is now hardly possible to deceive the casino, which monitors every behavior of the player, so cheaters use everything in a set.