@Big Daddy
Sorry to hear about this shyt breh
First: Have you confirmed that your health insurance company actually denied the claim? It's not uncommon at all that you get a bill before your health insurance company processes it on their end. Call your insurance company and make sure that they are denying it before you do anything else.
Second: I'm a personal injury attorney. You probably don't have a case. Sounds like a clear cut, and pretty egregious misdiagnosis, but you have to prove that the medical mistake was the proximate cause of your damages. Has anyone told you that if you had been properly diagnosed an hour earlier (I think that was the timeline from your OP) that you wouldn't have had to be flown to the other hospital and undergo the same treatment you did? If so, then maybe you've got something. At least the bill for the helicopter
Medical Malpractice cases are very expensive and very difficult though (at least up here in MD/DC).
May be different in your area.
Glad you made a full recovery breh
Or if you end up filing a lawsuit I'm sorry to hear about your ongoing, life altering pain and suffering