Chauvin is a killer, plain and simple. The same as the cop who shot bobbitt is a killer. The difference between the two are, in one situation deadly force WAS AUTHORIZED, in the other case, civil liberties were infringed on and a citizen under the care of an officer died.
Since you fail to beleive he was choked, we can look at it as failure to render aid. Still guilty. So, either way, chauvin is guilty of neglecting his duties and it resulted in a death. Murder.