If this recent mva has exacerbated her conditions you need to make sure that you report the accident to her carrier and consult a local lawyer. With an intervening event your best bet is to look into that before any medical providers. A local lawyer will be able to guide you to providers who can help.
It sounds like your partner has several chronic conditions that, unfortunately, are never able to be successfully managed to 100% satisfaction. A TBI is a complex, barely-understood injury with loads of impacts. There is no magic cure. Likewise for bulging disks (sometimes a back surgery can help but MVAs tend to foul all that hard work up). Fibromylagia is a real tough problem in that no one really knows what causes it or how to successfully treat it. It is characterized by chronic and widespread pain. There is no magic cure.
Given these realities, it doesn't make sense that a physician may have missed something a few years ago and this single failure is causing all of her pain. Her condition is the natural progression of her multiple pain-inducing pathologies.
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