The bug I was writing about is tied to travelling back to Act 1 with or without her AFTER you recruited her. It occurred for me when I recruited her at Moonrise and then went to the crèche afterwards (without her). This was in a playthrough started about a week before patch 6 dropped. So this bug is not fixed.
Ah, unfortunately, I haven't been able to reproduce this bug. Prior to Patch #6, I took Minthara back to Act 1 using the Silence spell as per my friend's suggestion and I didn't have this problem. Yesterday, I decided to go back to the creche
without Minthara, leaving her at camp, and her battle lines seem to trigger normally when I got back to her in the Shadowlands. Maybe this depends on how you recruited her? I bonked Minthara for this save and the gobbos are dead.
You're not the only one though. My friend had this issue too a while back but sadly she already forgot the specifics. Please let me know if anyone else encountered this bug :'3