I am sure that the unknown is very scary. I can't imagine suffering for so long and having no answers. Keep at those doctors. With MS, your brain can show changes in a very short time. I once developed a new lesion in 4 weeks ( I am so proud ). If your last MRI was five years ago, it is time for new ones. Ask your doctor to order new ones. Keep asking until you get some answers. Good luck on your quest.
By the way, for what it is worth, my doctors never ordered an EEG as part of my testing. I had evoked potentials but not an EEG.
Keep us posted.
Love and prayers,