Hmm its possible that she is part of the same NPC faction as the guards and people in the Tavern. So killing her would make them hostile to you.
Ziroc will need to check her faction setting to see if indeed killing her mad her faction turn hostile.
BTW was the the Drow woman that was running away from the Drow hunting party (on Level 1) OR the Drow woman leading the hunting party (on Level 2)?
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