Can I enter this?

noou

It's up to the creator of the giveaway. You are supposed to ask him. If you win, he might ask for a reroll. But he also might not.

edit : but if you did won, that would cause 2 games to be forever lost... A bit of a shame, eh ?

You will have to ask the giveaway creator, it's up to him, but still it's a little douchie to enter if you have most of the games.