-it's pretty ridiculous--and much against standard protocol--for no imaging studies to have been done.

Generally, since neurological symptoms generated by problems with the central nervous system can exactly mimic those that come from peripheral nerves, one of the first/easiest (though expensive) things tod o is to get MRI's of brain and spine.

Considering all those other tests have come back negative, it does seem increasingly important now to check for brain/spine problems. These tests may come back negative as well, but they do need to be done.