Yes you are right that mate trying on sites without the list of casino that have announcement thread here on forum is very risky to play in my own opinion it because we don't know thier management if they are reputable casino or not unlike here in forum we already know what are the casino that trusted enough and we have a security on we play with them. So it is better to be safe a rather than playing on risky sites.
I can admit that I am very harsh with the casinos that do not have an announcement thread on the forum as I am basically treat them as if they do not exist.
There must be a few good casinos out there that do not advertise on the forum, but since there are so many scams casinos out there I am not taking any risk and I gamble only at the casinos which have a thread here as if something happened to go wrong and I did nothing wrong I know the community will back me up, and the pressure we can generate together will be enough for the casino to do the right thing, as most casinos are not willing to ruin their reputation over something so small like a disgruntled customer.