Not at the same time. He can let go of the sword with one hand while he uses the dagger or hand crossbow, but he can't do anything useful with it while he does so. He's "holding" it at that point, not "wielding" it.
Yeah doesnt work does it.
Looking to gain darkvision by weilding "Graefling" Bastard Sword and attack with CA thru that method with a ranged attack, but I dont think it will cut it.