Unprofesional and ********* Business conduct

I contacted Standard Bank Insurance for third Party damages Caused by a client of theirs. They were using Quest Solutions that act on their behalf, but the Digital assessment is done by them, They refute a claim because the initial accident was not caused by their client, but their client did not do enough to prevent her vehicle from hitting mine, and now they don't want to take responsibility, yet I'm the third party that should be claiming against them, because their clients vehicle was the cause of damage to my vehicle, and I do believe if their client did do enough and apply the teachings, when going for your drivers License, she could have avoided causing damages to my vehicle. I do believe that their behavior is very ********* as they don't take all consideration into account before they just make brutal assumptions and decisions