A common complication of such an incident is what is called a subluxation injury.
This is common in an automoble accident after so-called "whiplash".
Essentially, the vertebra, which are "stacked" on top of one another, become misalligned.
Hopefully this will not be the case.
The symptoms of such an injury usually show up from eight months to two years after the incident and legally, connecting the two can be difficult. The misalignment results in numbess and pain, typically of the arm and shoulder, but sometimes extending to the hand. Because of the pain, the patient "self-splints" and the range of motion is gradually restricted until they end up with a "frozen shoulder". The pain can be excruciating. Treatment is generally by manipulation through the range of pain, anti-inflammatories and axial traction.
Because there are possible (hopefully there will be none) life-long problems documention of the injury and consultation with an attorney at the earliest stages is necessary. You need to obtain copies of all medical records and physician's reports as soon as possible.
Obtaining depositions (or simple statements, the names of witnesses, and preferably a videotape) of the game should be obtained as soon as possible. A year from now nobody will remember anything, and the school board will state "nothing ever happened". It is important that you notify your medical insurance company that there is a potential tort and that the school has liability. If the bills go on the schools tab, you won't have your insurance rates raised (as is the case with some policies when you make a claim).
The tort liability exists because your son was permitted to continue in the game after an injury. That is a violation of the doctrine of the "reasonable and prudent man".
Now this is a litigenous society, and I am not recommending a frivolous tort. I am saying that there is a possibility (and only that) of a lifetime of pain, and the way the world works is that in such a case compensation is commonly awarded.
Treatment of the "hairline fracture" generally involves temporary immobilization. Theree are pro's and cons to a cervical collar. A collar can exert traction, which is contraindicated in the healing stages (it tends to pull the bone apart). At a local health food store get some so-called "bone tea" which is a thousand year old treatment.
Later in the game, if pain develops after the break has healed, axial traction may be helpful.
Certainly for the next few months, or a year, no sport activity that may result in a blow to the head (and sudden neck flexure) should be considered.
A CT scan is inappropriate (too much radiation) and obsolete. An MRI is the appropriate diagnostic tool. I am dismayed that a specialist "ordered some x-rays". X-rays show ungotz. X-rays were the appropriate diagnostic method in 1933. Having a radiologist "look at the films" is absurd. Upon suspician of a hairline fracture an immediate MRI should have been ordered without furthur ado.
First of all, his high-school football career is over. The liklihood is the hairline fracture will heal. But the injury cannot be agravated.
Secondly, this is an injury for which the school has tort liability.
Third of all an x-ray is totally inappropriate. He requires an MRI, preferably a 3T MRI. As of yesterday.
The l;idocaine does not "free up the neck". It was inappropropriate because the pain was causing him top self-splint, preventing further injury.
Forget about the funeral. They are dead and gone. It is out of the question for your son to be traveling with this issue unresolved.
Your son requires an immediate evaluation by a neurologist and an MRI.