My players just killed Carr but identified it as an attic whisperer. one of them was very curious as to why this thing was there, especially since it talked a bit to them and told them its name. He hasn't drawn the connection between Carr and Carrius, though.
Getting esoteric here, but that opens the question of the weapon's enhancement bonus and gp value. If a chain spear is a double weapon (or treated like one), then the +1 chain spear in the NPC's gear entry might be worth ~4,000 gp (2,000 gp sell) — if both 'heads' are +1 (which jibes with the +9 and +9 in attack line). Or, only 1 'head' is enhanced to +1, the weapon is worth ~2,000 gp (1,000 gp sell), and the listed attack bonus(es) for one hand or the other should be 1 lower.
I would argue, that only one head ist magical since the first part does 1d6+3 damage and the second only 1d6+2. Keep in mind, that every magic weapon by default also is a masterwork. That would explain the +9 to hit on both sides.