@MartinWL the point is not for you to start an appeal, but to allow your father to think he can do it. Let him do so but do not assist him. After all, he thinks he's perfectly capable. If the first point is to get medical evidence of fitness to drive, let him try and figure it out. If he can, so be it. From what you say, it will be virtually impossible for him to even get the medical evidence he is fit. If this hopeless quest keeps him occupied, well and good
As for the car itself, I still recommend hiding it if possible.