The problem with this class is if they get any kind of blinding, it would dominate melee's all together, it would take nothing to blind and order all rescue . And if its ney impossible to kill, all they would have to do is keep a melee blinded, same concept for mages, all they have to do is get them in a room with a strong npc and force them to focus fire.
I vote, do not allow the pet to rescue if its nay unkillable.