A number of points to make.
First is that with a prior need for an ACDF (fusion), your genetics predispose you to other level problems. Your symptoms fit with a C6-7 level problem (symptoms seem to be C7 root- see https://neckandback.com/conditions/symptoms-of-cervical-nerve-injuries/).
EMGs are generally not too helpful for cervical radiculopathy as pain symptoms will not show up on this test and motor weakness is easily found on a physical examination so the test would only confirm what is obvious on exam.
Running requires impact which can increase wear of any disc. There is no rule not to run but think of a disc like the shock absorber on a car. The disc can withstand repeated impacts but eventually can wear out with extended use. You would be better off as a swimmer, biker or gym rat (treadmill or even better-elliptical) with your neck. I don’t want you to stop but understand the repercussions of your actions.
Dr. Corenman
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.