I wasn’t in his shoes and don’t know how the old guy was thinking but I’m thinking he was scared enough to just make sure they were dead and it was his word against their bodies.
As far as combat is concerned and CQB in an environment like falluja with wounded laying around that may have weapons or body charges , some wounded are cared for and maybe sometimes they move funny and adrenalin takes over. But that’s what NCOs and officers are for to act as police. This old guy was by himself without that luxury. Maybe he got worried that he didn’t make a righteous shooting and wanted his words to be the only ones heard.
That is completely contrary to the evidence that he gave verbally, the audiotape of his activities that he made, and the forensic evidence at the scene.
He was not afraid, he was in complete control, and was waiting eagerly for the opportunity to do what he did.
Quite possibly. There is, however, a word that describes a killing committed in order to silence witnesses. That word is murder.