I thought she only appeared when you are captured by Gut, she's sent by Raphael, correct? She wasn't there last time I was in that area, it's been a while though since I looked around the cell area.
Confirmed with my playthrough. After killing the leaders / Gobbos (I purged the whole camp) including Minthara at Druid Grove you can find Korilla afterwards again in the cell. When I had attacked and killed her, she had simply disappeared in a cloud of blue dust.
