Car reviews shortened. Car has almost complete service booklet. Attorney thinks chances are bad

After an accident (the other side admitted guilt) my report was shortened by 1200€ by the opposing insurance company with the reference that my car was not completely serviced by the BMW dealer. The fact is that after the purchase of the car all repairs (the last one was only a month ago) were made by me at BMW, only the small inspection was done once at a free workshop, two months after the Tüv over BMW. In this small inspection nothing was repaired. Lawyer thinks that the courts (BGH judgement) only ask the liability insurance companies to pay the full sum of a brand workshop in the case of fictitious billing if they keep a checkbook. By the way, the first owner didn’t always wait for the car at BMW, but that can’t be accused of it, can it? Do I really have such bad cards? What do you think?