Glitch warning and solution: (credit goes to playstationtrophies.org)
You *must* make a save before you enter the room, just in case. If not, you'll have to go back to the last save before you entered the baroness' cabin.
I tried this 3 times, didn't pop; checked online for glitches and none were mentioned on xbox; however I followed the unglitching guide here:https://www.playstationtrophies.org/game/the-raven/trophy/77...
and it finally popped.