Cant create giveaways..missing game?

It's against the rules to giveaway a game that is different than what it says it is anyways. If it's not there, it's either there for a reason, or it could be a bug. Apparently, with this one, it was free for a bit.

Vanguard Princess was a free game for a time.

It was given out free in bulk, therefore you can't make a giveaway for it. Also you're on a good track - it's forbidden to pass it as a DLC :)
If you really want to get rid of it, I can suggest you to do it as a keydrop, or a reward of a puzzle, or just the classic " guess a number between 1 and 1000, closest one wins" game.

Well i jz wan to make a group giveaways that use this website doing the random choosing for me...im so lazy to do so. :P

You could make a puzzle from http://www.itstoohard.com/create

Have them pick a # 1-1000 or whatever and who ever gets it,will get the key

or https://www.random.org/

I can not see why some will say to lazy to do a simple little puzzle or key drop but can take the time to enter GA neither one takes much time.

Anyhow either way if it is missing chances are it was free at some point or maybe a exploited game.

See if anyone on your friends list needs it or wants it,then you can give it to them.

If its a key you can drop it in the group chat of your choice.

In the end there is no easy way to do it without some effort to be put into it.