I have another campaign that I started after hitting this bug and I just got to the same point and the scene worked. I don't know what is different. For my monk I walked up to the Zaethisk and Lae'zel did her bit about how happy she was to be there and I was explicitly given the option to let her go first. I got the persuade options to try and get her out. I'm a monk though so they're utterly impossible BUT they're there. I double checked on my paladin and druid which were both started back in September and those campaigns are still stuck with the bug.
