Since you car was legally parked when the other driver swerved to miss the cat and collided with your vehicle, it should be covered by the other driver's property protection (PPI) portion of their auto insurance policy.
In Michigan, what is known as PLPD (public liability and property damage) is basic insurance, thus just the minimum state required liability limits. There are 3 parts to the basic no-fault insurance that must be carried on a MI registered vehicle.
Michigan state law requires personal injury protection (PIP) of at least $10,000; property protection (PPI) and residual bodily injury and property damage liability (BI/PD). In the case of your collision it would appear that a claim should be able to go under the property protection portion of the driver's insurance policy.
PPI under Michigan's no-fault laws pays up to $1 million for damage a car does in MI to other people's property, such as building and fences. Usually other cars would not be covered but the exception is parked vehicles. According to the MI Financial and Insurance Services site, PPI does pay for damage a car does to another person's car if it is found to be properly parked at the time of the accident.
If your car is properly parked and hit by another car, the other driver’s no-fault coverage will pay for the damage to your car. So instead of the mini-tort amount of $500 you should be able to place a claim for the actual cash value (ACV) of your Mustang. This is usually determined by using a NADA guide book, Kelley Blue Book value, local area sales of your same vehicle and internal insurance computer software.