As someone that works in auto insurance claims this is AWFUL advice, OP don't listen to this person. There is a scary amount of misinformation in this thread from people who don't work in auto insurance and don't know what they are talking about. Cooperate with the investigation and speak with his insurance company, they are the ones that will (hopefully) be paying your vehicle's damages and your cooperation will make everything much smoother. I can't tell you many times I have seen instances where we are trying desperately to give money to someone our policyholder has hit, but they refuse to speak to us or help us with an investigation and just screw themselves out of reimbursement sometimes just through non-cooperation.

A coverage investigation means that the person that hit you may have not had valid insurance coverage at the time of the loss. This could mean that the car he hit you with wasn't the same vehicle on his insurance policy, this commonly happens when someone buys a new vehicle and forgets to add it to their insurance policy so the vehicle is technically uninsured. Another reason for a coverage investigation could be that they were an unlisted driver, meaning the vehicle they were driving is on an insurance policy belonging to someone else and they are not the actual driver of the vehicle as listed on the insurance policy. Whatever it is, it's nothing you /u/SereneFrost72 and is just bad luck if this asshole didn't have proper coverage. But I highly recommend you cooperate with his company and do whatever is asked of you within reason