Kantor on 21 February 2009
I'll answer the third one, from what I know about it.
Snake was designed to die at an early age, because he was only needed temporarily, and they didn't want him getting out of control.
FOXDIE was injected in him not to kill him, but to kill the deserting Patriots. At least, that's what Drebin's FOXDIE was for.
(Former) Lead Moderator and (Eternal) VGC Detective 
