Technically and literally, your vehicle is no longer insured at the time of said accident. Therefore, it is not possible for your vehicle insurance to pay for anything.
It is mandatory and a state law in Georgia, that every vehicle traveling on state roads and highways should have, at the very least, liability coverage. Liability coverage does not cover your vehicle, but would in this case, cover a hurt passenger or even cover another driver's vehicle.
Georgia Insurance Companies do offer uninsured/underinsured policies to vehicle owners for this very reason. The passenger in your son's vehicle is not able to make a claim against your insurance, because, simply, you do not have one to make a claim against.
The passenger has several options, if they have their own vehicle insurance they could attempt to make this claim with their own vehicle insurance company, although it is not likely that any insurance company will go for this since the vehicle they actually ensure was not involved.
The second option, is for the passenger to just have medical insurance pay for whatever pain or injuries that were endured as a result of this accident.
The last option for the passenger is the worst. It is the point at which the owner of said vehicle becomes personally responsible for any pain, suffering, and/ or injuries sustained as a result of this collision. This is most likely when the at-fault party is uninsured. The passenger can file a lawsuit against your son, and/ or whoever's name was on the title of the vehicle at the time of the accident. This matter will be called before the Court and the Court gets to decide, based on the police report and medical documents, if the passengers should receive compensation directly from you and your family.