Was he carrying a gun, or has that programme been terminated?
No, the program has not been terminated and he would have to have been qualified as a flight deck officer. I doubt he was, but if so, his firearm would not have been on his person when he went to the cabin,
Doubting is not certainty. I suppose that in order to prevent an errant 'flight deck officer' taking his gun into the cabin it would be on a piece of string not long enough to reach the cabin (sorry can't find an emoticon for light hearted cynicism.) He was evidently very worried by some form of perceived threat, he may have been worried enough to arm himself. I am not at all reassured by your confidence.