Nope. Not within the scope of his official duty . . .
His authority to carry was directly related to his employment as an FBI agent. LEO including FBI are on duty 24 hours a day, authority, and responsibility do not stop after the clock. Same goes for supervisors that is why when government servants make dumb comments on the internet they get punished, or fired. The issue of his unsafe handling of a firearm will come back to his training in court.