Medicare, Medicaid, Life and Health Insurance/Non-participating provider
This concerns my 93 year old mother, who has various issues as you might expect. I have experienced this same problem over the years in my own situation, but with her it is likely to come up again and again.
When in the hospital or rehab or nursing home etc., the doctor will refer her to some provider for some service or another. I even assume that as a custom or policy of the doctor or of the facility, some doctors will refer to the same provider without consideration of other providers. This is a problem when that provider is a non-participating provider of her Blue Cross insurance or Medicare. The expensive bill can come months later and it seems impossible to dispute that she received service, but it is obvious that there are participating providers available. So at the root of this is the question as to how to make sure such things do not happen, or if they do, she will not be liable for payment.
I definitely feel your pain. You need to ask if the drs are Medicare participating physicians or locate your Medicare contractor and download their MedPard directory which lists all participating providers.
And there is no reason why you cannot contact the drs offices's and ask them to write off the balances.