Parked Vehicle Damaged by Adjacent Construction Site

My vehicle was parked at my office on the top floor of a parking garage adjacent to a high-rise construction site. The vehicle was sprayed with a concrete substance. After I approached the contractor, they had a detail company attempt to remove the concrete but permanently damaged the paint. I obtained estimates to repair the damage, but the contractor stated they would only pay for work completed by a company of their choosing. They attempted to fix the damage with their chosen company, but not to my satisfaction. The construction company has stated they will take no further action.