The phrase "homicide with conditions" does not appear in Georgia case law or statutes. Are you sure they did not say "homicide by vehicle"? In any event, I have reclassified your questions under criminal defense as it relates to the criminal aspects of the case rather than a civil claim for personal injury or wrongful death.
I would never refer any client to a chiropractor. If a chiropractor is a modest portion of the overall chain of treatment, that is fine. However, I would never accept a case in which chiropractic is the primary mode of treatment. I have withdrawn from representing clients who refused to go to an MD. That is because in my observation jurors and insurers take injury claims much less seriously when the main treatment is chiropractic. Life is too short to waste time on such cases.
You are not responsible for the negligence of your adult son driving someone else's vehicle. If he were driving a vehicle you provided to him as a family member, you could be held liable under the family purpose car doctrine. If you provided a vehicle knowing of his poor driving history, you could be liable under the doctrine of negligent entrustment. If he were on some errand for you, even in someone else's vehicle, you could be liable under the law of agency. But if he was simply driving...
If you have collision or comprehensive coverage on this vehicle and cost of repair exceeds the deductible by a lot, and if policy is worded to allow coverage for this event, then it may be worth turning in. This is controlled by the contract. Your concern about fraud concerns me. You must be completely honest. I would not expect this to have much if any impact on premiums with your good record if you shoot straight.
The testimony by all the ER personnel would be that you were incoherent, combative and had to be restrained for your own protection. Jurors would have to choose between believing you and a whole bunch of medical professionals. How do you honestly see the odds of your success?
If your case in in Brunswick, there is good reason that lawyers turn it down. In the entire history of Brunswick all the way back to colonial days, apparently there has never been a jury verdict in favor of a plaintiff in a medical malpractice case. One local lawyer who incurred the wrath of the local medical community was blacklisted so that no local physicians would even treat his children. Moreover, at least 80% of all medical malpractice cases that go to trial statewide in Georgia are won...
Under Georgia law the claim for property damage is separate from the claim for bodily injury so that the property damage can be settled promptly. Check to make sure that you signed a property damage only release rather than a general release that could include the bodily injury claim too.
There is no automatic legal presumption against you, but as a practical matter I think you will lose this one in traffic court. I hope you have reported the incident to your insurance carrier, which will be obligated to provide coverage and a defense for the claims against you which are likely coming.