My very first job was working for Sohio as a pump attendant and mechanic. For those who don't know what Sohio was Google it. PArt of that job was repairing and mounting tires. At one point I set the record for mounting and balancing a complete set of tires in 12 minutes and that was done with a bubble balancer. Yeah, when a customer asked for a "special" service we did out best to meet their needs.
Needless to say I would NOT EVER let this ride. The technician screwed up and damaged your wheel, no if's, and's or but's about it, this was done by a technician not following established procedure for mounting this tire. Since they been Ghosting you I would go to the Small Claims Court and file a claim for damages. BTW in this case damages are the cost of a new matching wheel, which won't be cheap. However it will typically be less than 1000 dollars so it's eligible for a Small Claims Court filing. Once that is done make a copy or your paperwork and take it to the manager at Costco and present him with a copy for your filing "to act as a reminder that notice will be coming". Note, that will get him talking about a settlement and don't let him off easy. You want a check for a brand new wheel plus the sales tax on that wheel. In addition you also want a 40% discount on that set of tires you just purchased. Stick it too him and he will make sure that some future customer doesn't have to deal with similar damage. Yes, that tech will probably lose his job but that's not much of a loss. Because the very first thing he should have done after damaging your wheel was report it to management and own up to the damage.
