I was being carried by the copter during the Someone Who Can Help Quest on my other character, Lucidhunter-Hyjal, to unlock the Mechagnome race when my Dungeon Finder popped up that I was ready to enter a dungeon. I decided to enter the dungeon while being carried by the copter (mid-flight). When I finished the dungeon, the quest was no longer in my quest log, and there doesn’t seem to be any way to finish it or pick it up again.