Based on what? What is the demonstrated crosswind on that aircraft? What is the landing performance with some tail wind? Did the winds change so they had a component they did not already consider?
Contrary to what you have written, a gusting 35 kt crosswind/quartering tailwind, is a serious consideration.
I also disagree that there was any problem with the statement saying that if they didn't give them the other runway, that they'd have to declare an emergency. The capt was just trying to avoid the hassle for everyone if they declare. If they could just be reassigned without that, then no problem. However, they also may not have had the gas to do much. That is NOTHING illegal about ending up tight on fuel. Legal dispatch fuel is NOT the same as what is required to land. We burn into the reserve and alternate fuel not infrequently to land at the destination. It is a Capt decision. Happens much less often at my company than the pax carriers, because we carry a lot of extra fuel for dispatch reliability, but it still happens.