More than likely the officer will be in the right. The kid instigated the situation on top of hitting the officer in the head and arm with his baton multiple times . I have seen those break concrete with very little effort. Imagine what that could do to your head or arm?
Do I agree with how it was handled? Hell no! This officer is a cop for a University, you're going to tell me they don't have any non-lethal options? Just a gun and a baton? Police are trained with hand to hand techniques while they are in the academy, for situations just like this. Even though the kid was rushing him, he was unarmed and his arms were in the air. They said the officer had already gotten the baton back, no need for a lethal resolution. That is how I see it though.