Most points are valid, however if the a/c was that low on fuel then an emergency, at the very least a pan call, should have been declared a lot sooner. The pilot stating that they needed 31R or they would declare an emergency is not the same as actually declaring an emergency there and then. I as an ATCO would have probably done the same thing (depending on the traffic situation of course) while co-ordinating with the approach controller. This seems to be a common trait amongst pilots in failing to declare an emergency with the correct phraseology, the most famous being Houston we have a problem.
I can see the point of the pilots, however using ambiguous RT did not help the controller understand the urgency of their situation and maybe a refresher would be in order.
A better call may have been,
May-Day May-Day May-Day (Callsign) unable to accept RWY 22 due crosswind, request immediate vectors for 31R due (insert emergency of choice)
I'm pretty sure that would get the immediate attention and understanding of the controller to which it is directed.