Several points:
1. Don't ever give statements prior to talking to a lawyer or without some training and tactical strategy. You're every word is scritinized and you're hyped up on adrenaline. One stupid comment can be dissected by armchair prosecutors to infinity.
2. Don't shoot someone in the back unless you are sure they are simply maneuvering.
3. The 80 year old had a clean prior record, had been repeatedly burgled, and suffered a broken collar bone from the assault he received after surprising these TWO burglars who broke in to rob him and committed a serious and possibly fatal assault on this venerable man. Let's not forget he was the victim.
4. The entire incident probably occurred in under 60 seconds from the surprise attack, beating, and their flight and him retrieving the gun and the shooting. Put yourself in his shoes. He doesn't have the benefit of knowing how many, if they are regrouping with weapons, getting help from others, or even the extent of his own injuries. In my view, it's a very close call. Someone's back can immediately become someone's front as they produce a weapon.
5. The medical examiner has determined the woman was NOT pregnant. Surprise, she lied.
It is a shame that modern law (driving by liberal anti-gun politics) tries to twist and manipulate things like this to make the homeowner the villain, and the burglars the victims.
So, here's an interesting question. At what point, and who determines, when a deadly encounter is over? Can someone shoot you, and then turn his back, and you can't shoot him back? Someone stabs you with a knife and then puts it in the sheath, and claims to be pregnant, and you aren't allowed to defend yourself from further attack?
As a defense lawyer, I would argue that when outnumbered by adults 50+ years younger than him, and jumped and beaten with near deadly force, these individuals were fair game as they maneuvered for tactical advantage. He may have not had the mental facility or awareness at the time to not continue to fear for his life, fear for another ambush or counter attack, or fear for the man to return with a shotgun from the car. Their 'retreat' did not necessarily end the threat, and they clearly knew how to break into his home, so he did not have sanctuary there. (I have not listened to the whole audio, so perhaps he did make statements that address these points, so this assumes his statements did not address these points...).
While he didn't handle this in a textbook manner, I do not believe this warrants any criminal charges against the home owner. I think that deference should be given to the 80 year old homeowner victim.