Regardless of the circumstances, I would not have diverted the aircraft. If the FA refused one of my orders, and there were witnesses, I would do the following:

1. Inform FA that if my order was not followed, I would have him/her/it arrested upon arrival for interfering with a flight crew member in the performance of his duties. That is a Federal beef, so conviction would mean the inability to ever work for an airline again.

2. If FA still refused, I would see step 1 through to the end immediately upon arrival.

Carl