My apologies for the rude message above.
I won't be able to check it right now. I wrote a script to check if Vittorio is alive, and if not, a video will play. But again, I doubt this script will work...

Christian = 0 --I write this at the beginning of the script
function ChristianDeath()
if (heroName == "Christian") and Christian ~= 1 then
    StartDialogScene("/DialogScenes/FallenKnight/S3/DialogScene.xdb#xpointer(/DialogScene)")
    SetObjectiveState("prim5", OBJECTIVE_COMPLETED, 1)
    SetObjectiveState("prim6", OBJECTIVE_ACTIVE, 1)
elseif (heroName == "Christian") and Christian == 1 then
        print("Did Vittorio capture the Castle?")
        end;
end;

Trigger(PLAYER_REMOVE_HERO_TRIGGER, PLAYER_2, "ChristianDeath")