Won a giveaway, but the key for the game was already taken

So, after testing the key, i emailed him/her telling that the key was already taken. S/he said s/he didn't use the key and is offering another game for the inconvenience, what should I do? Since the games have almost same contributor value, although i liked better the one i won, i was thinking about accepting, but if i tell that the gift was received on the giveaway, someone may look into my profile and think that i am a regifter or other thing. Do you guys have any solutions? Thanks.