Nice way to avoid answering your refund request. They didn't even give a timeline so for all you know, it could be months (ala Hero update) before they release something. I know the cost is not worth the time to argue about, but I wonder if you went to the credit card and complained that they sold you a faulty product and want to reverse the charges, if enough people did that then visa/mastercard would flag that site and not process anymore.
For the cost of the game your credit card company will just automatically credit you back the charge. They have a policy about filling disputes unless the charge is a certain amount. And $5 is so low they will just reverse the charge for you instead of going through the trouble of disputing the charge with the merchant.