I'm assuming his mock Keyblade is fairly big (about the size of a regular-sized Keyblade, presumably), right? In that case, then no, it's unlikely he'd have that with him. The distinction is less about just what people would have on hand, and more about how it actually got there with them — a knife is fairly small and could've been in a pocket or a compartment in a bag, whereas a Keyblade is pretty big and more of a separate entity in and of itself, if that makes sense? (If it doesn't, I apologize, it's early and I'd be happy to clarify further if need be.)

He is, however, welcome to find things around the castle that he could use as a makeshift blunt weapon! It's just unlikely that he'd have that particular item with him after the jump.