Event hough the dialog is skipped, accidental or not, the npc should remain enough active to hint a wandering player. Instead of the whole dialog, he should remain slightly active to produce one line of text in fun way "Are you lost? Did you forgot to press the switch for the metal door?" M is definitely helpful, so it's good to have it. I don't recall seeing it in help? Maybe i went through it fast, though, it happens when I'm not fully devoted to a game.
What is your plan with launching your game, distributing, monetizing, and other publishing povs? Oh and last time i forget, what engine did you use for making it? Not that I'm coder but I find the engine important in the game distribution, and this isn't something i've run across before.