Since you are on base, you should make sure that the doctor has run the Revised McDonald Criteria to eliminate everything possible. If you are in the military, MS is a career ending disease according to the military manual. It ended my military career. You should have excellent access to qualified neurologists, but as MS is incompatible with the military, it might be difficult to get to see an MS Specialist. You might need to request a consult which the neuro can do by sharing your records with an MS Specialist. My original MS Specialist often consulted with different military doctors long distance.
The Lyme test if it is handled at a regular testing lab may return false positives. A VEP Test should be available at the base hospital.
Please let us know how things go and if you have questions you need answered. There is an MS Association in Japan, but they do not speak English. I translate some things for them. Some of the better Japanese MS Specialists are found in Northern Japan. I do not know any who speak English.