Uninsured Company Car Hit My Rental Car. Their Old Insurance Company Is Stonewalling My Insurance Company, And The Subrogation Process Can't Continue Without A Letter Of Denial

Location: Alaska

February 2026: I was housesitting for a friend when the house flooded due to rapid snowmelt. There was three feet of water in the crawl space and rising. The only business that responded to help was a "water damage restoration service" that came an hour after one the my friend's emergency contacts called them. They parked their truck at the top of the driveway, which promptly slid on ice and slammed into the back of my rental car (Enterprise) (my car was getting work done at the time). All of this was caught on video. We exchanged insurance information, the workers left to "go get something," and never came back. At some point they said they needed a letter of approval to work from the homeowner, to which my friend immediately responded with the letter of approval, and they still never came back.

It turned out that their insurance was expired and the truck was completely uninsured. Since someone needed to pay for the damage, my insurance paid the damage with a deposit from me to Enterprise (all completed in June 2026) with the intention to subrogate the water damage company. In order to do that, my insurance needs a letter of denial from their old insurance company stating that there was no policy on the car with their company at the time. However, they are refusing to provide a letter or respond to anything. My insurance company is still working on it, but I'm so annoyed at the stupidity of this situation, and know that there are multiple levels of unprofessionalism and incompetence.

My question: Is there anything I can do to expedite this process? My deposit was sizable and I would like to get as much of it back as possible, but also this is such poor practice that should not be allowed to happen (even for Alaska standards). Is there any group / organization I can / should report this business to?