Condemor, you ought to add the users listed in the 2nd half of this post to your Giveaways Blacklist (and the 1st half too, if you've got room for them):
forums.indiegala.com
(This message was prompted by seeing the outcome of this giveaway.)
Fake giveaways and scammers
@dblancog Sometimes it happens that I'm sure the key is normal, but it turns out to be used. Apparently those who arrange giveaways or key sellers make a mistake! When people come to me with such a problem, I always try to replace it with another key! But there are also bad people who do nasty...
(This message was prompted by seeing the outcome of this giveaway.)