Locked door in Raedric's Dungeon

[yupper]

There is a locked door in the north part of Raedric's dungeon, past the backers' tombstones, that I can't open. It cannot be picked as the "proper key" is required. Apparently, this is Osyra's room, but I don't understand why it is locked. I first encountered this door as I was clearing the dungeon. The only thing I had done prior to this was to free Giacco and killed 2 gate guards at the keep (before I elected to go through the sewer instead). 

 

I thought perhaps I would get the key to open that door after I've progressed through the rest of the keep, so I continued with the quest. But even after killing Raedric, that door is still locked (I have the key from Nedmar, which does not open that door).

 

I can't find any information about this. Any ideas?

 

[Edit]

Nevermind, I found the stairs on the east side of the sanctuary and made my way down to the room with the switch, which opened the door. Turns out it was just an empty room with stairs. Funny I never met Osyra as I was clearing the dungeon....just undead.

Edited December 3, 2015 by yupper

[Trexxenn]

that is weird, Osrya is just past the cells to the north, she has a nice grimoire on her, too.