The question
What would a .410 do with 4 shot at 50 feet?
I would say that if the guy's face was showing at all, he might be missing an eye, he might have had a pellet or two go through his ear, and any shot in the skin of the face would have most likely stuck into the flesh.
After carefully pulling out the shot with sterile tweezers and applying alcohol (OUCH!), the guy might live with dark spots in his face where the lead was pulled.
If the guy had on a light jacket and shirt, I'm sure some pellets would have penetrated the clothes and into his skin (more "tattoos" that the BG can remember).
Let's put it this way, I think there was GOOD REASON that only five of the six showed up the next day. It might have been OBVIOUS who the person was, if he had fresh pellet marks on his face, neck, hands, etc. I hope they all got the message not to mess with Gramps!