I had this bug and made an account just to let y'all know of a workaround for me:
Loaded up a quick save before the autosave.
Enabled cheat console (iroll20s)
Typed this into console: AreaTransition AR_LAX03_0101_Temple 0 0
My party runs up to where the bugged scene occurs. Another conversation will occur between Llengrath and Tayn, and then the bugged cutscene will play. It still hung for me, but I was able to move my party (it seems like coming into the room via console doesn't "freeze" the cutscene like normal). Once I moved around, the scene progressed normally. Everything else has seemed fine to far. If you're worried about achievements, download a mod off Nexus that allows them with cheats.
