Has he gotten any sort of physical therapy- or a comprehensive evaluation by an advanced PT, DC or osteopath (DO)?
These people study more of how the whole body works together , more than general MDs usually do.

If no one has a referral for your area , searching out experts in the fields I mentioned for your area might be the next step.

I hope someone can help you with some good names for Stockton, CA area.

Other thoughts--
His neck muscles could be in spasms - that could contribute to the headaches. ( muscles would be hard & not pliable like a normal muscle)
Trigger points could be a factor if there are small extremely sore spots/knots in the muscles.
Possibly an expert upper cervical chiropractor would be of help. The c1 c2 could have gotten misaligned and that can upset many things in the whole body alignment.
Also, possible pinching of the vertebral artery by the vertebra, or muscles in spasm pulling on things can contribute to headaches.

The care is very limited. They seem to simply give him medication and hope the problems fix themselves. I will look into the specialties you mentioned. The main issue is that the health care provider has denied any sort of second opinion or outside treatment, which could get costly. I know at one point he had injections in some of his neck muscles which slightly alleviated the pain. I do believe the muscles in the neck are under a lot of spasm. I will look into the trigger points as well.

James,

Rather than a Neurologist, find a Physiatrist listed in the Yellow Pages under Physical Medicine and Rehabilitation. Call them and ask if the doctor has good experience with concussions. The doctor with good concussion experience will hopefully have a Physical Therapist either on staff or in his referral list. As Jo*Mar said, he needs to have his neck, especially his upper neck (C1 and C2) evaluated. He could also have injuries much lower in his spine. Was he wearing a seat belt? This can cause a whiplash type of injury. If he was not wearing a seat belt, the more lower spine and twisting forces come into play.

At two years, some of his symptoms may be permanent. But, if there is unresolved injuries in his spine and upper cervical area, getting these injuries treated can allow for great improvements.

Is there anybody who can watch him sleep? He may not be breathing correctly when he sleeps. This can result in head aches and fatigue and massive mental confusion.

Hope he can find some help.

My best to you both.