Please show me at least one gambling site where changing DNS is prohibited, lol. Personally, I've played in more than 100 casinos over the past few years and none complained that i using google DNS.
I never said that they will ban you because of changing the DNS server. In fact, no one who knows what DNS server is and how it works will say that. You can change it to whatever you want, you don't even have to use one if you add the website's ip to your hosts file.
What I said is that they will ban your account if you are from a restricted country or a country where gambling is illegal and the trick in OP won't help.
Also, I never said that online gambling is illegal in my county, just country decided to support local bookmakers by restricting access to foreign casinos.
That's good but OP's situation is different. I believe he is from Indonesia and gambling activities are illegal there.