You arrive in a room with 3 locked doors. A group of 5 servants of the Menagerie are in this room. Kill them, this will open a door.
Enter that door and kill the 4 denizens of the Menagerie, this will open a second door in the first room.
Enter that second door and kill the 5 bedchamber attendants, this will open the last door for the first room.
Enter that last door, move through the corridor up to the Shade of Tobrin. Kill it and his 4 Menagerie guardians. Tobrin is Level 45 ^^ Heroic, his minions have no pips, but heroic.
You then need to look into the chest to get the Eyepatch.
You'll find T'Lys with 6 minions. They are level 45 ^ Heroic. Kill them. T'Lys will escape but you will have the Eyepatch.