yeah, to get hin on the ground lol not twist his ankle or injure him. You practice BJJ? He could have added for more torque than what was applied in that video...he's def trying to get him down on the ground. If he had a history I'd probably lean towards your view, but the guy doesn't have a history of doing that.
Occamz Razor. The simplest explanation is likely the right one....he was just trying to make a tackle.