Well, his timing sucks then. It still looks like regifting. He hasn't given away any other games immediately after winning it, so why start now?

And you cannot tell what copy he activated anyway.

I've bought old bundles, then won games here that were in those bundles. So I asked for a reroll. Not give away the game immediately. At least he could have waited a couple of weeks. I BL anyone that makes a GA for a game they just won (when it had 1000+ winners) right after they won. It's too fishy/ too much of a coincidence.

Any keys I had acquired after I won I would wait a month or two, unless I was giving away most of the bundle.