The victim allowed the suspect to pick up the weapon? He should have immediately emptied on him at that point.
Most people in our society have an aversion to killing another person. It comes from Christian culture. Lots of non-Christian cultures do not have such an aversion.
I wouldn’t want to kill him either, and neither would most folks. I am not into hurting or killing any thing.
But after the suspect was shot, the second he bent over and reached for the weapon on the floor, I would have emptied on him, without hesitation.