I have no clue how to advance this quest. I've seen and read that
killing everyone completes the quest. It didn't do that for me.
There is no one else to talk to. Long resting does nothing as there are no NPCs left to come back to the building because I already took care of them all.
It's been something like 6 hours total I've been trying, desperately, to get this quest to finish in my journal. If anyone can help, or confirm my game is just bugged, please let me know.
I've got this bug now too. It seems like it's not doing the "We interrupted the baddies having a meeting, now we gotta kill them all" step, thus actually killing them all has no effect because it's not looking for that condition yet.
Funnily, when I first arrived in Act 3 and the lower city, I happened to fly up to the third floor and I remember I *did* get that journal update and was instantly aggro, but I didn't keep that save as I wasn't really ready for it yet. That took place a couple hotfixes ago, so not sure how long this bug has been there, but I'm definitely stuck now in exactly the same place as you. I've even done all the same possible remedies over a few hours to no avail.
Also, after arriving and getting the 2nd floor password, if I just go up to the third floor I can walk around freely without aggro. Unless I talk to someone at which point they all aggro but there's no journal update. I can listen to them talk about the pipes and whatnot all day, and nothing. If I pick up and move barrels around they'll look at me sternly then pick the barrel up, lol. So weird. But they don't attack me unless I attack first or talk with one of them.
So it's just stuck there for now, I guess.
