First off, the video:
Expected behavior: stealth through the quest using the ballista and a high jump score, finish with no alarm raised and 1 mob killed: Matador Chieftain.
Actual behavior: stealth through quest, no alarm ever raised. Once I was inside the Chieftain room, I used the wand on the two runts in there to avoid the alarm. Stealthed to the corner behind and to the right of the Chieftain. I had to kill Matador Chieftain. I chose to kill the 3 Cabal Seers, the named Orc and Ogre Magi, and 5 trash mobs that aggro'd on me, because otherwise their healing would have outpaced my DPS on the Chieftain. I still got the stealthy opt, but that trash insta-spawned on me no matter what.
Any ideas on what's caused this change in behavior? This happened after the last update/patch, as I had no unexpected issues soloing this quest the last time I was running it.