What's the word/phrase:hunter's remorse

Factual Questions
1

My friend who’s a copywriter has asked if I know of a phrase to describe the moment when a hunter, at the moment he gets his prey in his sights, suddenly loses his nerve or has a change of heart and can’t bring himself to pull the trigger. My friend seems to think such a phrase exists but can’t recall it. So far all I could come up with is Clampettitis (remember the scene where he’s “shootin’ for some food” and lowers his gun?) or Bambi syndrome but these don’t seem to be what he’s looking for. Thanks in advance to the TM.