[SSDan]

So sorry to hear this. I assume this is the same shop who declined to share the cam card on their secret cam grind. I'm not capable of giving you much legal advice other than to say you may well need to hire an attorney to push this issue. Round up every speck of documentation you have especially anything with that shop's letterhead on it. Print out any email or text exchanges you've had with this shop and write down every phone conversation you have had as best you can remember. Documentation always becomes important in legal/contract disputes and if you hire legal help they will want it as the basis to build your case.

The lessons I have learned in this space from personal experience and from friends is why I always use a credit card or PayPal for payments made in advance of service. These payment methods give a recourse and path to dispute the charges and get you money back.

Good luck - it sucks to get stuck like this. The shop has all the leverage until you can find a way to apply pressure.