In order to make sure that an online casino is reliable, it is recommended to check it on recommended sites that deal with reviews of online casinos, such as Askgamblers and Casino Guru.
Still, you fall again within the realm of trusting a third party about the legitimacy of a third party, it is kind of a redundancy if you asked me. It would be more productive not go to directly for a centralized platform to seek for information about casinos but focus on communities like this one, in which anyone with certain level of experience and reputation could give you their own opinion and appreciation on the casino you are interested in.
I am not implying those websites you talk about and ill-intented or anything like that, but it is not a good practice to completely trust what they say. I have personally seen how good review webpages have been corrupted by services like scam casinos for them to get promoted, since I experienced it, I rather to open a thread in this section and openly ask about a service, instead of reading and review webpage...
Just my two Satoshis, though.
Doesnt matter on which source of information that you are really that getting into as long those things will really be that real but if you are really that in doubt then it will really be that common sense that you will really be making out some indepth research about on various informations that you had been able to read up. We do know that not all words that we could be able to read online is really that something true or legit. On the moment that you would really be gonna tend on dealing up with something then it will really be best that you should really be validating it or in doubt then asking up some questions into this forum alone
will really be or should be enough when it comes on trying out find out whether that site you are talking into is something that can be trusted or something which is new and people here on the community will
really be giving their outmost or sincere responses but of course you should be careful with those newbie responses as well.