Talking to Stingtail for the cook's stolen goods didn't trigger Sebille's dialogue. I went back to the cook and refused to turn Stingtail resulting in a fight and killing the cook. Back to Stingtail, the dialogue triggers, killing Stingtail as a result and now the quest is stuck on "The local cook, Griff, should know more".
Reading more on Divinity 2 wiki comments, found that Zaleskar is the next person to talk to. Playing for the next 2-3 hours in hopes of talking to him would progress the quest, it didn't.
Any fix?
