I've handled claims in several states and I'm not aware of any time limit for reporting a auto accident. Police departments are generally required by law in most states to file a record of all reported accidents. If the department says it is to late to file a report send the police chief a letter by certified mail return receipt requested stating the facts of the accident and the fact that someone in the department refused to file a report. Be sure to list any known witnesses to the accident.
The fact that he is no longer with the same insurance company is of no effect as the company that had the coverage at the time of the accident is on the hook for coverage. You need to contact the other driver and ask him to report the collision to his agent that wrote the policy in force at the time of the wreck. If he won't you can report the claim to the insurance company, but be prepared for the insurance company saying they can't do any thing until their insured reports the accident. If they do that send the insurance company a letter by certified mail return receipt requested addressed to the claims department stating the facts of the accident. This should cause them to at least set up a claim file and contact their insured. Be sure to keep a copy of all letters you write and keep the delivery receipts when you get them back in the mail.
If you had collision insurance on your car be sure to report the accident to your agent. If the other company will not pay you can collect from your company which will then subrogate against the other company to get their money back and likely your deductible also.
Call a local lawyer who specializes in auto accident claims and ask for a free consultation. Most lawyers who handle accident claims will visit with you once for free. If the first lawyer you call will not take the time to talk to you call another. This is situation where you ordinarily should not need a lawyer and your are in a bad position where the cost of repairs to your car likely will not justify the expense of a lawyer. Nevertheless, most good lawyers in the personal injury/accident field will visit with you at no charge and give you advice.
You should file a claim with your company, and obtain a local attorney to sue him and find out who is insurance currently is if any. Usually the insurance on the date of the accident is the policy that will provide coverage.
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