I don't think that "fear of his life" is required for it to be considered a self-defense shooting. However, there must be some evidence available, other than "two men, one dead"! Damage indicating forced entry, perhaps, or the dead man was armed. These would support the occupant's report of what happened.
That's why it's a question of fact, to me, rather than of law.
Agreed on all points. I knew when I posted it some one would point that out but I'm just too lazy to type out "fear of bodily harm, theft, defense etc." :)