Glitch with wolf Hitbox ?

Hello, yesterday I pulled on someone who has used this technique:

This player has to kill a wolf, and then hide behind that prevented me from touching it with my gun.
I think this is due to the hitbox wolves is not correct.

A picture to give you an idea of ​​what is happen:

What do you think?

I think this is because the hitbox doesn’t update when the wolf falls down, so it’s as if the wolf is still standing up.