@Snapple2020 has posted some great information about fighting for insurance to cover a person outside of their coverage area - here’s one link that doesn’t have a lot of info but does suggest you can fight Medicaid to get the coverage you need since your situation does seem “catastrophic”, & if there are no doctors in your state who can/are willing to help you, then you have no choice but to go out of state.
If you click on the magnifying glass icon & type in: out of state insurance - there are a number of posts that come up. You may be able to get more information by reading a few of those.
I’m so sorry that Dr. Case wasn’t cooperative. So discouraging!!