Exactly. If there was any question then the punishment is way too permanent to even be considered. But this dude is literally the father of a 14 year old girls child. There is no question here. There is no ambiguity. Have a third party double check the tests and another one tripple check them; if the results are still conclusive then make sure he can never harm anyone ever again.
My only complaint is that castration is cruel and unusual without reason because it doesn’t actually prevent him from being a danger. Just lock him up forever or kill him. Right now I know life imprisonment is usually cheaper than the death penalty otherwise it wouldn’t even be a question.