He was resisting arrest, for which force is necessary, and there wasn’t especially brutal force in that context (although honestly, as someone who doesn’t often watch violent scenes, the whole thing was disturbing to me). So I don’t see any imperative to indict.
Politically, these things usually get classified as a ham sandwich, but legally, I don’t know enough to think there was any kind of mistake. I don’t think you do either, unless maybe you’re a criminal lawyer (is that redundant?) and not telling us.