I would guess that the locals thought the victim was the attacker. This happens a lot where the public are willing to intervene in a crime. Even the police sometimes assume the wrong person is the perp.
As far as Naples goes, however, the locals have been known to try and brutally feed you to death. One couple I knew there had his-and-hers kitchens. I had to take a 3-day fast afterwards just to get hungry again.
Oh yes, and you cannot escape overland, because every tiny town is especially proud of some dish and some wine and it will take you 10 days to get 20 miles@about 2 pounds a mile. You'll never make it to the Rome airport alive.