While the automated checks are secret like hechelion said, please make sure you follow the quality guidelines, in particular point 1: avoid publishing your page before it's ready. I suspect a lot of people get impatient, and it could be a reason why this keeps happening.
Maybe it was unclear, but the game was initially made for a game jam, so.......... It gets published when the deadline of the jam is reached (doesn't really have anything to do with impatience in my case).
I also recently got an answer to my ticket from the support, and apparently it could have been caused by the fact I had an other page of the same game with restricted access for private testing purposes ? I am not totally sure, tho. Either way, the sanction from the algorithm was a bit disproportionate compared to the reason it got flagged in the first place. If I can suggest an idea, having different degrees of flagging before putting a page in quarantine could be a better solution ?