Regarding dogs digesting raw bone, most dog's GI tracts can cope easily with bone. Dogs new to raw may need to adapt as their systems are used to pellet + soft food.
The stomach acid is so concentrated that it breaks small pieces of bone down. But if the dog doesn't chomp food into small bits larger bits of bone may remain. That's why its important not just to feed bone, so it passes with other digested material.
I don't see bone in my dogs' poo, which indicates their GI tracts are ok at breaking it down into small *kickable poos. (*Copyright tedsmum)