Haven't you been listening? No, I very much doubt we would be having this conversation had Kel'Thuzad formed the staff. Kel'Thuzad holds the head. His underlings hold forty splinters of Atiesh. The last piece - the base - was uncovered by Brann Bronzebeard. He was last seen in the Silithus desert; undoubtedly doing his best to stay as far away as possible from the relentless seekers Kel'Thuzad has dispatched into the world.