Maybe you'll just have to wait until a new sx shows...that or the Optho/Neuro will find you've had ON, but the VEP's should have shown that. Other tests you've not had would be the Neuro/Psychological Exam that lasts all day, tests everything, and costs a bundle. Then, I think you are done....no more to do.
There's hope for answers, but you may have to wait. You can't demand an answer

If the test don't show it, they don't show it. I understand

...maybe it wouldn't hurt for you to chat with a therapist like I am doing. We just never know until we tried everything, and if it's not anxiety, then it's not...and you'll have proven it!
Criteria seems to point to the fact that you'll need another seperate exaserbation (time). The current one you seem to have will have to work its way to remission and then, who knows, you may go years before anything else happens. When and if it does, you will then have more ammo for the doctors. My flair lasted about 6-7 weeks, with residual going on for a few weeks after that. So it should end soon, or I hope it does.
Meanwhile, I found when I was numb, if I didn't pay attention to it, I forgot about it for the most part. I was numb the whole left side, so I get it. Are you just numb or do you have strong pins and needles too? (Like asleep?) Not that it matters, just curious

I also found that cold wind on my skin felt good...so if its cold, maybe a walk outside or a drive with the window open blowing on you? Just things that worked for me
Take care of yourself...it's going to be okay