Unfortunately, I don't have any other saves. I've just been hitting quick save. I've tried zoning in and out, and restarting the client, but nothing seems to trigger the fight. I've been trying to see if this game has a debugging console or something, so I can give myself the helmet or make the NPCs become hostile, but this game doesn't seem to have one.
However, I didn't immediately port to my tower after finishing the quest. I remember exiting the tomb and handing the quest in, at which point I saw those NPCs in formation. I thought that a cutscene might trigger if I walked up to them, but nothing happened. I thought nothing of it at the time, so I just quick saved and then I left.
I'll go ahead and email support to see if they can help at all, but I won't hold my breath. Anyway, thanks for the help and the timely responses, I really appreciate it!