I had a similar experience. After passing the poison/fire areas on the way in, I entered the Ancient Abode and went into sneak mode with all of my party. I turned out the torches as I encountered them, so the whole area was heavily obscured. I did not encounter Auntie Ethel, but was able to free Mayrina using the control globe and looted the workshop without encountering the hag. As the point of this is to fight the hag, I then went out of stealth mode, turned on all of the torches and wandered around the ancient abode knocking into things. Eventually I encountered the teleportation portal at the back of the workshop, which put me back in the bog, but did have a fight with the main villain. Where is the hag?.