How to Use/Invoke California Surprise Medical Billing Law?

My wife gave birth to our son late last year. We went to an in-network hospital and hit max out-of-pocket from the charges which I paid. In September of this year, I received a bill from the doctor that delivered our baby. Insurance paid $0 and applied the bill to my out-of-network deductible limit for 2021. Does the California surprise medical billing law apply in this case if I have medical insurance through my employer? Can I or should I fight this with the provider? I appealed with my insurance company and they just sent a form letter stating “we process based on information provided and doctor/group is OON so it gets applied to your OON deductible” with no further information.

I’m confused because technically the charge is “covered” because they applied it to the OON deductible which is MUCH higher than my in-network deductible. The doctor also shows up in UHCs in-network portal but this claim was billed under a provider group and not the doctor’s name. I guess I need to call the provider group but I already assume they will just say “too bad, pay it.” I don’t have a problem paying doctors for their services, but I feel that in-network hospitals are pointless if all the providers are OON. Delivery is not really a circumstance where I can research the doctor and make sure insurance is in place.