For the first clip, i can remember that, and i did hear sound, so that is it, shots in the head there is nothing i can say, just aimed.
The second clip, the dude is literally stuck, in straight line, how would i miss? I don't know about recoil, but there was no way to miss....
The video in the rooftops, what is the suspicious act? There was a guy bent over not moving, i killed him, and the other guy came out while being shot.. i just kept waiting like the other guy inside the building did...