Work Comp laws do not vary that much from state to state. They came about when the employee's right to sue his boss for his injuries were taken away, and in place of that (there were too many law suits) workers were given conpensation (usually a percentage of the normal wages,) for work related injuries.
Insurance people who only do work comp often become bitter. The files that they work stay around for years and years, and, frankly, they are always dealing with cheats and liars so they are suspicious of every claim.