Hello @ndttech, welcome to Mayo Clnic Connect. I've not heard of Wharton's jelly injections for PN but I did find some information that may help. I'm not sure there has been any clinical trials for stem cell therapy for peripheral neuropathy. There have been a lot of clinics popping up all over the country touting stem cell therapy treatments which is why the FDA put out a warning. I think stem cell therapy holds a lot of hope but I don't think it's quite there yet. I would want to see some extensive clinical trials that show it works.

FDA Warns About Stem Cell Therapies
-- https://www.fda.gov/forconsumers/consumerupdates/ucm286155.htm

Porcine Wharton’s jelly cells distribute throughout the body after intraperitoneal injection
-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5813394/

Long term effect and safety of Wharton's jelly-derived mesenchymal stem cells on type 2 diabetes
-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4997981/