We know it's not ceaser because in the "factions" video you can see the courier talking with the guy.
and theres a big change it's mr. house neither due to the fact you can meet him if you work with him.
Which leads two likely canidates
the NCR president Kimball.
and
Benny(the guy who shot your character) will surely die aswell unless he's killed by other means which would count as you not killing him.
two part question:
Will nameless NPCs respawn if you kill them same as fallout3 or will they stay dead forever making it possible to literally kill everyone almost.
