Sorry to hear your ride was damaged.
Sadly, the cop misinformed you…
It specifically states in the rules that the church is not responsible for any damages that may occur to your vehicle at the cruise. It’s the same thing when you park in the parking lot of a department store. All car cruises and car shows are like this. Enter at your own risk. If you have a high-caliber car or bike and are worried about even the smallest mishaps, I would not leave it unattended.