Won game - game in bought bundle - give game?

There won't be any problem as long as you activate the game you won.

As long as the won copy is in your Steam library, you can create the giveaway.
Even creating this thread will probably earn you some blacklists. Don't worry about BLs too much :)

Ask yourself this question: Do you really want to win something from a person that jumps so quickly to the conclusion that you might be a regifter?

I would assume that the chance someone blacklists you is pretty low, anyway :)

You can give it away without being afraid of that, the regifting is always biggest when there has been a giveaway with many copies.
Aslong as the wins are activated on your account as been mentioned, no worries mate!! :)

I don't think it is a problem. Most people don't check the list by hand. They use the SGTools. And if you have activated it you are clean. So no need to worry. For example I have won Journal on the 31th of July 2015, activated it and played it. Then decided to share the game myself, bought it and made a giveaway on the 2nd of August (merely three days later) and it doesn't seem that any of my blacklist entries comes from that fact.

If you activated your game you are most likely sure. And the two or three people who don't pay attention and blacklist you anyway shouldn't bother you.

I thought about that when I gaveaway Mad Max from Monthly Bundle like month after I won one few weeks earlier.

In the end I thought nobody cool is dropping blacklists without first doing even basic SGTools check, so if any BL happen, it will not be from someone cool anyway.

Just don't delete game from your library in a fit of rage and you'll be fine :P

Explain it on the giveaway description