It is easier than you think. The player has seen the arm of the model thus can easily extrapolate the position of rest of the body and kill the player.
Imo it's not a matter of predicting the position of the enemy, it's a matter of shooting patterns. I personally wouldn't tap that at short/cw , short is so closed ranged ... it's so easy for terrorists (especially when there are multiple terrorists) to wallbang you back whilst spraying. It's just not a position where one would take the time to tap and reposition.
I obviously do not know what went through that player's mind but he seemed to care more about the reposition (aka saving his hp/life and calling for feedback according to say_team) than actually facing the T offensively. And if one moves tapping is usually the way to land your shots with higher accuracy than spraying.
If a more agressive options like spraying wasn't chosen it may even be because this player is not confident with his spray control, who knows!
I can hear some footsteps that clearly show enemy location in the video.
but some shot like wallbangs(even wall bang through smokes) or crosshair placement doesn't make sense.
either he's lucky and using s_max_distance 100 with decent headset/phone or he's haxing on and off.
chances are haxing. too good to be true
omg it was not shikari in the video...
I don't think he's even playing anymore and the game was on a ukrainian server as you could see on the video, so it makes no sense.
Some strange situations (knowing when enemy will appear and thus preaiming mainly) but overall the suspicious ones are, as far as I understand it, are where this player does very precise wallbangs.