> What do you mean “he doesn’t take responsibility”?

It's probably an issue of poorly chosen words, but compare

> fourteen months later I shot a man and unfortunately caused his death.

with

> fourteen months later, I shot and killed a man.

The way that it's currently written sounds like an accident: "I, a victim of PTSD, shot a man and, in a bizarre twist of events, he died from it". The passive voice there paints a disconnection between the cause and the effect.

Of course, judging a man's life from two sentences is nonsense. It just so happens that those two sentences are very unfortunate. But that's on the editor.