Yep this happened to me, too. I lowered Mayrina and she walks out of the cage but I can't talk to her and going into the hag's room does nothing because it's completely empty. Not sure what to do at this point.
Edit: I'm wondering if the reason why this got hosed is because I
1) went straight through the fireplace and didn't get entangled with the bloodthirsty goblin dudes
3) figured out that the door was fake without putting on one of her masks
2) snuck past all the thralled people with masks on and didn't engage with them either
Maybe if I hadn't tried to be sneaky and followed the script it would have worked? I don't know....
I followed the same steps (except I killed all the masked guards) and got the same result. (Mayrina is bugged and can't be interacted with)
