They have consistently not made calls when players are tripped up but the puck was touched.
Given the fact that colour commentators comment that it's not a penalty, and the fact that the NHL Rulebook says "Accidental trips which occur simultaneously with a completed play will not be penalized" as well as "If, in the opinion of the Referee, a player is unquestionably hook-checking the puck and obtains possession of it, thereby tripping the puck carrier, no penalty shall be imposed" I'm guessing that it's not referees missing a call.