Road to Ruin happened as a NOTW because at the time mafia was defined predominately as a clue-based game. Mine mostly followed traditional NOTW aspects (no talking at night, items, story-driven, victory based on NOTW strength conditions, PG's, etc) but differed in two key aspects: it was not FFH based (which I got some flak for from the FFH diehards) and the roles were not public, limiting roleplaying possibilities as cover roles for mafia was not yet a thing. Had the game occurred after ATPG's conversion of mafia from clue to standard, both Road to Ruin and Impending Retribution would have more than likely been classified as mafia.
That all said, it's up to King Morgan if he thinks his game will be more NOTW than mafia. Personally from sign-up thread alone I'm leaning towards it being a NOTW style game - the setting certainly fits it but he knows his game better than I. NOTW's don't always have vampires in them and in fact for a long time didn't; prior to oyzar's NOTW XXVII I don't recall them in any games I played in. It's all dependent on which setting within the FFH universe the game is channeling.