It drives me crazy when companies hit the "third party" button. I paid for Turbo Tax services. I did not contract with a third party and it's ludicrous that you are saying "you didn't have an arrangement with our third party, but now it's your responsibility to contact them; you paid us but the problem is no longer ours."
Your hiring a third party should have no effect on the services for which I paid and it certainly doesn't exonerate you from blame. I'd suggest you re-examine your third party relationship. In the meantime, you should be doing everything you can to admit blame and make some kind of compensatory gesture. Anything less is a mark on your product and a bad faith gesture that says "once you pay us, we farm out responsibility and therefore are no longer responsible if there is a problem with what you paid us for."
