A surgeon should have never done ACDF if he can't see spinal cord compression on the MRI. Did you get other opinions? Have you had other tests? Yes, MS is another possibility but many other things have to be ruled out before having spinal surgery. ie-B12 and D deficiency, MS, ALS, Lyme etc... Now, just because one surgeon did not see enough spinal cord compression on your MRI does not mean it is not there. I was misdiagnosed by 3 specialists before 2 other specialists said my symptoms were from my neck and after my own research I agreed and had the surgery. Now, ACDF surgery is not always guaranteed to resolve your symptoms. I have heard of rare cases where symptoms do not resolve or they get worse and the longer you have had the symptoms the greater the liklihood of permanent spinal cord damage regardless of the surgery.
I am not a Doctor but have the said anything about Multiple Sclerosis(MS) There are several test that can be done to help diagnosis this. Good luck and God Bless