No, because they don't portray shotguns realistically in this game. Why should they pay a knife to the head realistically? A shotgun can one-hit-kill you reliably at 30 yards in real life, but in this game people have whined enough that they've nerfed do much that you have to be 6-8 inches away and get a headshot to one-hit-kill someone with a shotgun in this game. So, no a throwing knife head shot shouldn't be a one-hit-kill.