This quest is a little buggy. Don't follow the bloody trail until after youve gotten credit for "Locating it." If it gets stuck, just make sure the shades are on and you walk in and out of the room the first blood splatter is in until you get credit. This seems to be the most finicky part.
You'll get credit for following the trail when you make it to the upstairs of the Legerdemain Loungue.
Make sure you are stealthed before you go in the room in order to get credit for listening to the SI:7 dialogue. If you forget, just run out of the room and back in stealthed.