I purchased a bundle in a recent sale, and had one of the games, so I just purchased the other three. I was under the impression that you could get single keys if you already had a game. When I try to redeem the bundle, it shows one of the three games, and it's the one I was hoping to gift. Is there any way to redeem the other games first so I can gift that game to someone else?

Normally when trying to redeem gifts containing several games there is a checkbox next to each game which let's you choose if you want to redeem that game or not. So normally you should be able to just select the game you want to redeem and leave the others.