What this illustrates to me is the wisdom of the advice I was given in my Nevada CCW class: when the police arrive, say nothing more than "I've done nothing wrong here and fully intend to cooperate with your investigation, but I intend to say nothing about this incident until I have spoken with my attorney. I'm sure you understand".
One difference in this case is that the criminal demonstrated a willingness to actually fire his weapon without provocation. As such, the expected number of people who would have been killed had the criminal escaped was likely greater than one.
In both cases, I would regard traumatic factors as justifying the good guys' behavior. In one case, the good guy had just been shot in the head; hitting 3 times out of 17 shots wouldn't be great marksmanship under normal circumstances, but for someone who was just shot in the head it doesn't seem too bad. In the other case, since the good guy hadn't been expecting to find himself in a situation where he was armed against a criminal, he cannot be faulted for not having perfect judgement in such a situation (even if his judgement was imperfect).