What if Haye still runs around the ring like an headless chicken then? I think it would have to be a tko.
What should the ref do? Counting to 10 is pointless, so you just stop the fight. So is that a KO or TKO?
Removal of head is not a legal boxing tactic, so he'd at least lose a point. The subsequent tearing off of any other appendeges would certainly result in a DQ, a fine, and a reprimand from the boxing commision. Kind of like Tyson-Holyfield II.
The referee would have to ask the severed head if he wished to continue, and if not, or he got no answer ,it would be a TKO. But...if the rest of the body fell, and was counted out, thats a KO.