Why are police writing traffic reports on private property? IME, this is not the norm.
The police report should state what kind of damage was observed on the pump. If it states that there is no damage to the pump, then your "friend" is good to go. It would be hard to prove that your "friend" did that damage after the fact if the police report states that there was no damage to the pump that jumped out in front of your observant "friend".
I used to handle these types of situations all the time for State Farm. The police report carries tremendous weight.