https://www.youtube.com/watch?v=sKx87hyWzQA

See timestamps in video description as well as below for specific items of interest:

Suspicious moments:

0:57 - Moderate snapping, ultra steady cursor during kill

8:17 - HEAVY snapping during parachuter kill 

12:34 - moderate snap, ultra steady cursor during kill

12:52 - ultra steady cursor during kill

It seems to me that this is a case of possibly manual aim to get very close to target then assist while actually firing. Unnaturally steady, too many kills with too few rounds fired, etc.

JUST to be sure it wasn't some affectation of the spectate mode, I went ahead and spectated a random person in the same helicopter in the gunner position on the same map. Check the subtle cursor movements when firing rather than a 'lock' that's common in the primary video. This vid starts at 3:50 and includes a few kills. 

https://youtu.be/r3kW-v_oM2A