He couldn't lift his hands up because he got kneed really ******* hard in the liver.
This breaks down Kikuno's crescent kick. You will notice that when he hits his opponent with it his body hunches over, his arms drop, and he can't raise them back up to even attempt to defend the punches.
There is also often a slightly delayed reaction in this happening. Hopkins/De La Hoya for an example.
Duffee's legs clearly went out from the last punch as well.
Thats a good point it was the Knee that seemd to spot Duffee from fighting or even trying.
As for his legs going, I never questioned the fact that the KO was real, Overeem connected there is no doubt but that is not prof that it was not fixed, Duffee could still of left himself open to take that shot as real as the shot was, if you where going to fix a fight that woudl be the best way, a fake shot WWE style would get caught out, actually letting your opponent KO you is a much more effective way.