Limp can be caused by either, so my first step would be to verify tire diameter uniformity. . PSI would be the first step.
I would also do a freeze frame on a DSO scope of the sensors, but I assume you do not have that, so start with the simple possibles ..

Rolling tire diamter can be done by marking each tire with a chalk and ground reference line and pushing the car foward and measureing the ground traveled. They should all match within reason...if they do , then sensor scopeing would be next step..the codes are telling you the module has detected a speed sensor circuit problem..it is NOT neccessarily telling you there is a bad sensor.

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A Dalton