If you bought it from a friend I fear there is no help for you. If the organisators would replace such things, anybody could go there and tell "my dog ate it, may I get a new one?". (Not that I don't believe you, just saying there would be tonns of such claims, if they did that).
Didn't you insure the ticket? You can insure stuff when you send it by post. With a Wacken ticket I would highly recomment you to do that.