A driver merged into me, their insurance denied my claim

Hello, I need advice on what to do.

I was driving in the right lane towards an intersection with two lanes. The lanes were right turn only, and left turn only. As we approached the intersection (less than 1000 ft.) a driver merged into me from the left turn only lane w/o any indication. It's also worth mentioning that the driver did not want to trade insurance, and we had to call 911 to the scene (I requested the 911 call, the body cam, and the incident report). He also did not speak english, so we mostly spoke through an app, and I requested his insurer make those records available as they corroborate the above.

My insurance told me to call his insurance. His insurance told me that it sounds like he's at fault, and that they would call him and get his side of the story.

Then without any indication, they denied my claim, saying that I was 100% at fault. Here is the denial letter:

"We’re committed to assessing each claim quickly and fairly.

After careful investigation, we’ve determined that our insured was not legally responsible for the accident. As a result, we won’t be making any payment. Our decision is based on the following:

Our investigation concludes the driver of your vehicle did not exercise ordinary care to avoid an accident that might cause injury or damage. It is the duty of the driver of any vehicle using a public street or highway to exercise ordinary care at all times to avoid placing the driver or others in danger; to use care to avoid any accident; to keep proper lookout for traffic and other conditions to be reasonably anticipated; and to maintain proper control of the vehicle.

Please call me if you want to discuss this decision or you need further information."

I called to ask for an appeal, and all they did was give me their supervisor's number, who has not called me back. They would not tell me what the other driver said, and they would not tell me what from the photos or location of the scene indicated that this was at all my fault, much less 100%.

I've never been in an accident before, and there was literally no way for me to avoid this driver. It's kind of shocking to me that either he or his insurerer would shirk responsibility, and I'm not really sure where to go from here. Please let me know how I can recoup on the loss this other driver caused me.

I will post pics of the location of the scene and the damage to the cars.

ETA: Also, the other driver told the police that I had merged into him. That can't be what he told the insurance company, because that makes no sense (we were both turning right, and the damage is entirely on the left of my car). But I can't fathom what he told the insurance company that would have them thing that I am at fault here.