I have run into this as well.
Some time after the Githyanki fight at the Mountain Pass gate, when I removed Lae'zel from the party she became unable to be interacted with outside of attacking her at camp. I cannot talk to her or bring her back into the party.
If you kill her, the quests related to her are marked as "She died" and go "completed" status. She cannot be brought back through scrolls or the Talkative Skeleton.

This has happened on two separate games. But I only realized it was after the Mountain Pass mission as I kept Lae'zel in the party almost the whole time on my first game.

After some experimenting I have found that this can be avoided if you DO NOT bring Laezel and confront the githyanki on your own. And then use the map disc yourself.
The moment you bring Laezel to this encounter and return to camp, removing her from the party will cause all of the above problems. This will, however, lose you out on a chance for story dialogue and laezel approval increase chance.

Last edited by Tialune; 21/11/20 05:44 PM.