Sergeant Daelione does still spawn at loc -3800, 2951 and roams through the zone from there. I'm not 100% sure but I think he gets killed by Dark Elves and golems when he roams. The quest still seems a little buggy as the first time I killed Daelione, Vekis did not spawn. The second time I killed him, Vekis did spawn but when I turned in the implant, Straeven did not spawn. The third time was the charm and everything worked. Straeven also spawns at -3800, 2951 he may also be a roamer, I'm not sure, I had a friend there when I spawned him to kill him instantly. This was on Bristlebane server. Respawn for Daelione was between an hour and 2 hours for me, and I was able to sit my 48 Iksar Warrior at his spawn location and just wait for him. There are a couple other NPCs that spawn there, but no trouble to kill unless you're worried about High Elf faction as they give a -75 hit if I remember correctly each time you kill them.