How do you know he doesn't just have high sensitivity
i have a g903 and even with it's dpi cracked up to that speed nobody could meaningfully control a snap shot that took less than a few frames. moreover their ability to play got quite notably worse once i started spectating. as you may know, cheaters can be notified when they're being watched. and while it's speculative and not a clear indicator its still worth mentioning during spectating they often traced people through walls that they had no way of otherwise seeing.