Fully inspect the rest of the steering system including the pump, hoses tierods etc... It may be that another part of the system failed first causing the accident. My guess is the accident may have caused the shearing of the shaft. Did the passenger tire take a hard hit? Check the box for cracks.

It would be hard to think the shaft broke on it's own, It takes quite a bit of pressure to shear it off. How is the truck generally used?

Also ask your guys if the steering went loose or did it get hard?