Really? Having been on the employer side in California, an at will state, for over twenty years, I am a little familiar with the way it is supposed to work and how the system is usually applied.
I too have been on the employer side for over twenty years and have been to a number of hearings. My impression is that the civil servants that act as judges in these cases tend to lean strongly in favor of the employee. In many cases the judge rules incorrectly in favor to the employee. However, if the amount is significant, I would bring in an employment attorney and have the ruling appealed. I never lost such a case.