I’m so sorry for your journey so far, SickRN! 🙁 I remember when I thought I was developing MS — it was tough to get answers! If your MRI is clear (and stays clear) I agree that it must not be MS.
Do you know if you have POTS? Do you know how to do a “poor man’s tilt table test”? Maybe that would help to get you some answers! big hug…