It is rumoured that most of these review sites are owned by online casinos and they pay people to give good reviews of their sites. You have to remember that these sites are not regulated like most of the brick n mortar casinos, so it is bit of a wild west out there now.
Bitcoin's annoymity are helping these sites to hide most of these activities, so you should not even bother to take reviews on these sites seriously. I would rather suggest that you signup for these casinos and test them for yourself.
Relying with those reviews wont really be ideal and as being said it would be better if you do just test waters on your own and judge for yourself if its legit enough or not.
I have not seen any casino, good crypto casino use these methods to try to make it self more visible to the community and the few ones that may have done I am sure they don't exist anymore.When you try to throw trash at your competitor by using shill accounts you will only damage yourself by doing so as the community already knows who the best casinos are.