Decided to run DFC a few times on follower difficulty to attempt to farm the trinket for the Mechsuit quest for if/when I eventually get the drop. So far my experience has been that when the first boss, Ol’ Waxbeard, is pulled, the NPC tank refuses to get any aggro for the first 10-20 seconds. It doesn’t matter if I pull with a standard mage opener or if I pull with Spellsteal; for whatever reason, the tank ignores the boss for a long time and prioritizes the adds instead, only eventually getting threat via ground AoEs. I can’t even invis aggro to the NPC because this particular boss has truesight.