Private Giveaway with 1 entry is legit?

Walmart

They can be obvious attempts at gaming the system or, as is my case for a few group giveaways, just not a lot of interest in the game. However, they don't count for contributor unless you have 2 entries minimum.

The game's value is not added to the contributor's account, and if I'm not wrong they can get banned for even attempting to do this.

It could be that the person shared the link with people other than the winner, but they already own it/not interested in the game? If its abuse, it'll mostly be a high value collection and they don't know that one entry giveaways don't add to your value.

Only think that may not be legit is if winner didn't activate the game (what you can check on your own).

A puzzle giveaway can have just one person solve it, for example.

I copied a link to a giveaway on that strange community wall thing, and only one person entered. Happens.

Of course its legit. We have a private giveaway group where we sometimes get 1 entry because nearly everyone who wants the game has it already. Obviously some people will try to exploit this but as mentioned, you need 2 entries before it counts to contributor value.