I am an adjuster. In some states, if car seats were not in use they don’t have to be replaced. If you think you can repair it then brand the title and get it repaired. Older vehicles get totaled due to the actual cash value. Head up. Everything will work out.
I looked up the guidelines on the carseat and this should be considered a minor accident so they shouldn’t need to be replaced. Airbags didn’t deploy and no impact on either side next to the carseats so good to go! So that is a positive.