Hello!

I've been thinking about the issue for few days and I would test CAN circuit before the controller, and after. Actually the steering system is on left/right side ise quite simple. Also open covers for wheel and actual steering angle sensors and swap L & R sensors if possible., we had one full of metallic dust that drove the sensors giving bad signal. But given the errors start with 0, and not 3 the issue would be on the side of combination-controller <-> steering controller. Check the plug pins 2-5(XB 174 PLUG) and XB 175 pins 2-5. Also XB300's no 26 and no 5.
If its matter of software, I would expect encoding related error or error starting with 6.

Software can be patched, but not by service techs.
Given that you failed to provide us s/n of given machine I cannot help to confirm your further suspision of different controller versions.