Not your problem. If he feels its unjust, he needs to figure it out. I got towed once, signs were posted and they towed before they started business, I parked in grass instead of taking a parking spot. When I called towing company they told me to call in 30 minutes since my vehicle was still in tow, cost me about $150. I didn't dump it on my parental unit(s), I was still living at "home", I took care of my mistake myself.
Nothing is free, someone pays.