I have some knowledge of this, as I work in Physical Medicine and Rehab, and I also had Cervical Radiculopathy.
First, the phenomenon that he is most likely experiencing is “Text neck.” It’s something that is so prevalent now, due to gaming and smartphones. It’s entirely postural, and it could be that he has some anatomical issues going on in his neck at this point. I was just told by our rehab peds doctor that text neck is becoming alarmingly common in children, and they are developing issues (arthritis, buldging discs, pinched nerves) as a result. If you have cervical neck arthritis as a child, you are likely doomed to surgery before you are 30 without intervention.
Have him ensure he has good posture. His head should not be leaning forward, and he should stop looking down at devices. This includes bringing the smartphone or device to EYE LEVEL! Next, all monitors, including TV, should be brought up to eye level. He should consider a standing desk for his keyboard and mouse should be slightly below the level of his elbows. Laptops are bad if they are indeed on your laps or even on a table. They too should be raised to eye level.
In nursing, there is an acronym called “ADPIE” (Assessment, Diagnosis, Planning, Implementation/Intervention, and Evaluation)
Assess/ Diagnosis
Go to the doctor and get assessed, and receive a clear diagnosis. They need to figure out EXACTLY what is wrong (Herniated disc, bulging disc, pinched nerve, mass, fracture, etc). Intervention without diagnosis could lead to greater injury. You must get imaging to ensure that there isn’t something more sinister than poor posture or cervical disc degeneration. Did he get imaging?
Planning
Plan on making changes to your lifestyle (posture, exercises, lose weight, etc). Reduce gaming time, or change posture during gaming as I mentioned above. There is a great app called “Lumo Lift” which uses your smartphone and a small device to monitor and coach you into proper position. It alerts you when your posture is bad.
Plan on physical therapy.
Plan on doing prescribed PT exercises.
Set an alarm to do said exercises.
Intervention
PT is the best intervention. If you don’t have access to adequate healthcare do to money/insurance, then go to youtube or google and look for “Cervical Exercises” “Neck Pain Exercises” “Mackenzie Exercises.” There is a lot of content and video out there for you to choose from. Remember; get your doctor or PT to sign off on these exercises first! You don’t want to do more damage!
These exercises are designed to add flexibility to the WHOLE spine (not just the neck) as well as to strengthen accessory muscles for better alignment. The flexibility and mobility of your spine only happens with a “wet” or hydrated spine and the discs are getting proper blood flow. When someone has a “dry” spine due to poor mobility or poor poster and thus a straightening of the spine (leaning the head forward, looking down, and sedentary lifestyle) they will develop arthritis and disc degeneration or a bulging/herniated disc. Remember, the entire spine needs hydrating and mobility. One level effects all the levels so likely you will have to do exercises for your lumbar and thoracic regions as well.
I literally set an alarm on my smartphone to remind myself to do my exercises every day.
You mentioned that exercises he was given did not work, however these things take time. It's not a over-night cure, and may not resolve for weeks or months. He has to be patient. Also, the exercises are only as good as the patient doing them.
I would recommend he actually go to a PT.
Evaluation
Monitor how he is doing with the interventions and exercises. If something is painful (and it’s not expected) stop the exercise. If the exercises are not working, make sure you follow up with your doctor.
In parting…I do NOT recommend a Chiropractor unless you are recommended one by a physician. Some chiropractors are great, some are dangerous. In the US, a DO (Doctor of Osteopathy) is the same level of practitioner as an MD, but with additional schooling in chiropractic and physical medicine and that would be your best option. Acupuncture might help, but PTs can do dry needling as well.
Best of luck to your friend.