Moral Question, Moonbeams

So I rent my car out via Turo. The deal is that basically while it's out of my hands during the rental window, the renter is responsible for all tolls and fees.

I got a notice in the mail from City of Philly Parking that there was an $80 parking ticket for my car during a time a renter had it.

I contacted Turo to tell them. They said to pay the ticket, show proof of the ticket and the payment and they would charge the renter.

The renter then sends me a message wanting to know what this charge is for. I sent him a photo of the ticket. He claims that he doesn't deserve it because he was in a parking lot the whole time. I checked the car GPS. He was in a parking lot.

It's possible, though, that he was there outside the hours he paid for, or something like that. That's what the ticket indicates.

If I do nothing further, I get my $80 back, he's pissed and never rents my car again. I could try to fight the ticket, using whatever evidence he can furnish me of the parking slips he paid for. But a) it's in Philadelphia and b) the ticket is already paid. I can't get a court date since it's already paid.

Am I under any obligation to do anything other than sit back and get my reimbursement?