I'm no labor lawyer, but I believe it is possible to get a lawsuit such as this dismissed on substantive or procedural grounds pre-discovery depending on the specific law, statutes and/or regulations involved. Yes, it can be challenging because for purposes of Rule 12 Demeo's allegations are accepted as true, which means the argument has to be that based on those allegations there is no actionable claim under whatever law is involved here. Also SJU would be somewhat limited in what documentary evidence they could submit in support of any such motion; usually anything incorporated by referenced (or submitted with) the Complaint, anything the Court could take judicial notice of and/or that might be publicly available is fair game.
Demeo's lawyers threw in the allegations about the Moore situation primarily for leverage, as opposed to his substantive claims, because SJU doesn't want that stuff out there, even though some if it was already publicly as it relates to Moore. He wants a quick and early payout. Will be interesting to see how SJU and counsel plays that. The Powell Seton Hall lawsuit is as damaging as you can get from a basketball perspective, and that is still out there (I think a motion to dismiss certain or all of the claims on procedural grounds was filed).