@engineer,
Their "distracted" excuse ranks up there with "dog ate the homework". But I don't know what they were doing.
Once contact was re-established, Air Traffic control instructed them to make a series of un-necessary turns in order to confirm that they were not being hijacked and were actually in control of the aircraft.
The flight recorders have been confiscated. I find it hard to believe that a "heated discussion" could prevent pilots from responding to repeated radio hails.