We're talking crazy people here. Their logic is not our logic. When Assam ended Murray's batshit crusade, he checked out before she could make the choice for him.
You know what? I don't care at this point. She, Jeanne, stopped this deranged killer...that's the fact. At the end, she may have shot and missed, she may have not shot...at the end, the guy died precisely because of Jeanne's heroism.
Either way, the public was saved the cost of confinement and trial...and this killer went on to stand before his Maker, and that judgement is in His hands. Jeanne saved many lives, Jeanne was a heroine here, plain and simple, and IMHO, placed there by the hand of God through His inspiration to her, which she had placed herself in a positon to hear, and which she then acted upon.
If this was a case of "death by armed woman security guard", or death by his own hand because she had stopped him, or death by her final shot...the results are the same, and for the same reasons. That's how I see it, and how I will pass it on to my kids, grand kids...and if I live long enough, to my great grand kids. Though I think the two intervening generations will make sure it gets passed on that way in any case.