Rainboe,
As long as the captain and the purser weren't pulling each others hair out his diversion seems somewhat unnecessary to say the least.
This is a multicrewed flightdeck on a plane flying on autopilot, it is not that the captain has to fence off the purser while he is struggeling to keep it in the air at 600mph.....
The mere fact that ANYONE, regardless of rank, diverts for not getting his paperwork on time seems like a very wrong way of personally getting back at someone.