Welcome Alena.
Sorry to hear you are on the dx merry-go-round for so long.
With four "O" bands and a strong history of neuro signs . . . MS could be a possibility. Many of the symptoms you have listed do seem to indicate some spinal cord damage . . . however, it is a little surprising that they haven't found any lesions after this length of time.
Have you had clear attacks with remission (not necessarily COMPLETE remission)? Were you in an "attack" when they did the testing?
Cherie