Animal abuse is no joke for sure. However, I'm not sure that it rises to the level of repetitive child sexual abuse. Also, I agree that a chimp would fight back and it would be a heck of a fight.
 
My dog would attack and cause great harm to someone who went for my Mrs or likey Me - 
As Most People’s dogs would.
Their owners sometimes abuse their dogs without them attacking them 
It’s quite possible it was like that with his monkey.
Though him being a weirdo Peadophile I don’t see the connection 
There may well be a connection between animal abuse & being a Peadophile 
Though I’m not aware of it.