Sounds like a crappy sword.
A ball bat would have worked as well.
Oh well. Kudos to the kid for busting up the perp.
Many injuries from sword play in Medieval times were not cuts but broken bones. It worked fine. One swing and the attack was stopped.
My son bought one of those crappy swords at Mayfest (Renaissance Festival, actually).
The handle broke off!
Looks from the video like a junky katana. The handle came off. Not a good sign. But heh, like you said... all that ends well...