In the absence of any structural/mechanical failure being announced, and finding it almost unbelievable that crew wasn't capable of handling the crosswind, I keep coming back to a C of G problem.
We all know how accurately final load numbers can be and I'm thinking an aft C of G would explain the lack of rudder and nosewheel authourity. Not normally a problem that causes such disastrous results but this fin did have winglets.
I know next to nothing about the 737, Does anybody know the overall C of G impact caused by the winglets on this type. I have heard the design required forward ballast be installed to maintain the ground envelope.