Trying to change things up a bit I was running some NMD for obducite. A key for the Sealed Archive was next in my inventory so started it up.
After the first set of rooms there’s a locked door that requires a key but the elite that was supposed to drop it was on the other side of the door. I had Subo as my mercenary so I could see an elite, not sure it was him, but I went back thru the entire starting area and there was no monsters and no key.