I'm familiar with how it feels to be at the wrong end of a dispute like this, but I think it's important to tell you that it would strengthen your case if you had shared more information about your attempts to contact them. Did you call? Or initiate a chat? How did it end up resolving? The thread you have only confirms the beginning of the problem, not the middle or the end.
EDIT: my motivation here is to tell you honestly what would strengthen your case. There is no upside for me in this conversation. I'm not affiliated with namecheap or any other registrar, and am merely offering my perspective: as a happy customer, I can be moved by other people's bad experiences, but they must be well documented. If you don't like hearing that, then ignore it.
Their support basically ignored any evidence to the contrary and let my domains expire and be sniped by other buyers.