Insurance requires photos

About six weeks ago, my car rolled onto my neighbor’s van (Toyota Picnic). Except for a few scratches in the paint on the bumper at my neighbor’s. I reported the damage of my insurance, because I was responsible for the rolling car and my neighbor drove to the workshop. There was a new bumper ordered. This then apparently arrived after a long delivery time, as my neighbor drove around with the scratched bumper for a whole five weeks. Yesterday my neighbour asked me if I had photos of his car, since the insurance now wants to see some, but he and his workshop didn’t make any. My neighbour said one day after the accident that the workshop had to replace the bumper because it had broken. I then looked at this again carefully and could not detect a crack or break. I then found this out to my insurance company. Can the insurance company refuse to regulate the damage because there are no photos available? After all, the workshop could have exchanged more than necessary. And what if the insurance company does not want to pay? Can my neighbour then demand the money from me? In addition, my neighbour told me yesterday that I had to pay the rental car that was due to him, even if he did not use it. Do I have to pay here or my insurance? Thank you for your help in advance. Greetings Tim.