Simply put, my wood elf rogue managed to avoid triggering the Auntie Ethel script, and break rescuing Marilyn's script by sneaking to the control orb and activating it, thinking I wouldn't have to deal with the whole burning cage nonsense. Afterwards, I couldn't talk to Marilyn (or whatever her name is) or get Auntie Ethel (who was very much alive at this point, having fled through her fireplace during her second turn of combat in the first fight) to appear, meaning the quest was broken and unable to be advanced.