Hi, I had the same problem as everyone else (started playing TW3 this weekend, so 1.11 for me too). I went there, managed to kill 3 ghouls *I think, can't remember* and nothing else happened. Tried everything listed on the entire internet as possible workarounds for nothing.
Today I started a new game just to check if I could get the POI to be completed and this is what happened:
Saved the game far away from the srine - as soon as I went outside the inn and brawled with those guys.
Went to the site and found 3 ghouls there.
Passed through them leaving them alive and went far, far away. Saved and got my way back there to find zero ghouls. Loaded, tried to meditate and went back there to find, again, zero ghouls.
Reloaded from just outside the inn back again. Went there and faced the, again, three ghouls that I found. Killed them, and went far, far away from the site. Saved. Loaded. Went back there (no meditation) and found the last ghoul.
Killed it and POI completed.
So this is how I managed to fix it. Hope this info helps anyone who's trying to get the POI completed and/or starting a new game and wants to get it done.
Hopefully it'll gonna get patched some day.
Cya