Use Expediator III to get to this mob. Good tip: If you see there is a spider spawn in the room with 5 mobs before the T-section going into her room, unless you have an enchanter, leave the instance and get another one. Bard puller will get snared and die, you won't clear fast enough with an FD puller.
Best scenario is after clearing this room, there are no see invis mobs in the hallway going into her room. Once you make it into her room, just stay there and keep the area cleared and farm the spawn. This is not a safe area since see invis mobs spawn frequently around here.