None of the mobs in this instance are see-invis, and the entire instance can be done in about one minute invis'd. Easiest of the series. Alternatively, if you can absorb the hits you can just train the mobs while you run around clicking for updates and deagro on the climbable walls. -Amezuki
the second time you're in the court, be careful not to zone out before you inspect the case as it updates the "you have escaped" portion of the quest and then won't let you in again to complete the quest properly.