Steam: Can a game recieved as a gift, be sent back after a short play

I purchased "Don't Starve Together" on Steam (which gives you 2 copies by default), I sent one to a friend as a gift who installed and played it for a short time ( < 2 hours). They decided that they didn't like the game and don't want to play anymore.

Can they now reject the gift, so that I have that copy again to send to somebody else? If so, how can they do this?

I think it should be possible if your friend asks for a refund, and then you ask for one as well. It's explained in this article on Steam support: https://support.steampowered.com/kb_article.php?ref=6643-QEUV-0459

1. The gift recipient should go to help.steampowered.com and log in with their Steam Account.
2. Once logged in, click on "Games, Software, etc.".
3. Find and click on the gift in the provided list.
4. Click the problem that is occurring with the product.
5. Next, click "I'd like to request a refund".
6. Finish the request by clicking the box to remove the gift from your account and allow the original purchaser to request a refund.
7. If the gift recipient has not initiated the gift refund process, you will see the following when attempting to request a refund.

Once the refund is done, you can request your own refund and then repurchase the game to gift to someone else.

Note: it is possible that this doesn't work with this particular game bundle because you probably played together and thus together have more than 2 hours playtime. Still, I'd recommend putting in the refund request.