I too work for Flybe. Don't know the Captain involved, but if it had been me sat in the RHS, I would fully support him/her in whatever decision they made. Not only do you have to think of the safety of the a/c and it's self-loading cargo, but also the comfort of those travelling. If I had paid a fair amount of money as a passenger, and ended up being surrounded by a group who were noisy and 'unruly', whether drunk or not, I wouldn't be too happy.
If the a/c had departed with the unruly pax, and a situation had developed in the skies, the Capt would have been the first person to receive a telling off from all those who know better - but who weren't actually there and don't know the full story.
Unless anyone on here was actually there, and does know the full facts, don't criticise.
To the Capt involved if you are reading this -
