It doesn't matter in which order you kill them - I just ran past them, talked to Zandalor, whizzed past them again on my way to the door with the password - looted everything in there - ignored them again, grabbed everything lying around and returned to Z. In one part I was surrounded by them - so I drank one of the countless shadow potions you find there and left them puzzling.
My mage couldn't use magic to kill them..
Kiya, coward
