Only 1 person has mentioned the cabin crew. What were they doing?
The argument has got to be rubbish. Sounds like 2 guys knowing they are in the crud going 'crap, we'll say we were arguing, that'll sound better'.
So assuming they nodded off (and I make no judgement, nearly been there myself a million times), did the rest of the aeroplane not start to wonder why they were an hour late?