In all my years of excessive drinking I never had a blackout and the only time I didn't remember what happened to me was when my head hit the pavement (concussion and fractured skull). I was told I functioned for a couple of hours afterward before going to bed. Even the next day I did not remember hitting my head and only when I discovered blood in my ear did I go to the hospital and find out the head damage. Slowly started remembering things days and weeks later but never remembered everything that happened.
Head injuries cause wierd stuff. If he got whacked, he may not remember talking to another operator as that is "auto pilot" stuff, trained into you.
The truth will come out.