Your experience is unfortunately pretty common. There is research that indicates that a lot of the various neuropathies are related to mitochondrial dysfunction

You might want to try some of the supplements that have been shown in research to help your mitochondria power the small fiber nerves in your body ( presumably clean EMG, clear Spine/Brain MRI's and sensory symptoms point to small fiber neuropathy). These supplements are Alpha Lipoic Acid with L-Carnitine, COQ10, and nicotinamide riboside. They are pricey but the first two have a proven track record and nicotinamide riboside has shown great promise.

Here are some links:

Alpha Lipoic Acid:

Supplements for Neuropathy: Vitamins and More

COQ10:

Coenzyme Q1 prevents peripheral neuropathy and attenuates neuron loss in the db−/db− mouse, a type 2 diabetes model
Prophylactic and Antinociceptive Effects of Coenzyme Q1 on Diabetic Neuropathic Pain in a Mouse Model of Type 1 Diabetes | Anesthesiology | ASA Publications

Nicotinamide Riboside

Nicotinamide Riboside, a Form of Vitamin B3 and NAD+ Precursor, Relieves the Nociceptive and Aversive Dimensions of Paclitaxel-Induced Peripheral Neuropathy in Female Rats - PubMed


Good Luck