So you participate in a giveaway and receive a working key for exactly what is advertised in the giveaway? I'd suggest you take the time to familiarize yourself with the rules of Steamgifts as outlined in the FAQ and Guidelines.
If you go ahead as you're announcing here and mark this giveaway as "Not Received" this is considered Misuse of Giveaway Feedback which results in immediate permanent suspension. Just saying so you don't come after it happens to complain.