The way the rudder system is designed makes it difficult for one servo control to be pulling one way and the others the other way. Of course, it could happen if maintenance makes a mistake when connecting the cables, but in that case shouldn't it jam the"bad" servo?
I, also, don't like to drivel before a thorough investigation is done. But my experience and the images incline me to look at corrosion problems on the composite material.
Most of all, I would like to congratulate the crew for the excellent job on putting this baby on the ground.