If you're an employer in California and want to choose a provider that will not have to deal with this you might want to consider offering Kaiser to your employees. There's benefits and drawbacks, but one of the big benefits is that they're vertically integrated and the doctors, labs, pharmacies are all part of the same organization. I would think that would help avoid this specific type of situation.

The big drawback is that your employees would need to live near Kaiser facilities. In the Bay Area they are everywhere though and easy to get to. Making use of any doctor or service outside of the Kaiser network is probably not covered.