Normally when you borrow a car and have an accident, the insurance on the car you were driving is what pays for damage that you cause. What makes the situation more complicated is that you own the vehicle that was hit. It's likely that your company would be the one paying for the damage to both vehicles, so you should contact them if you want to file a claim. Of course you do have the option to pay for the damage out of pocket
and that will likely help you and your relative avoid a potential rate increase, but that's completely up to you. I would recommend getting repair estimates first to help you make a decision.