More specifically, the attack on the TG base happens as it should, but since the journal entry is stuck at "Vals Varano is dead" (stage 150 I think) killing all of the attackers (as I had in the image) doesn't actually let me finish the quest.
Only the player should be able to do this; activating the door opens a message box asking if the player would like to knock, which isn't right and makes the dungeon a pain.
After killing of the scamps (reflected in Atreno's dialogue through the blocked door) and escorting him outside of the dungeon, Atreno initiates dialogue with me to complain about scamps still being present, which shouldn't happen unless he is still in the dungeon and scamps are actually present. Speaking to him afterwards seems completely normal however.