Create giveaway using AMD rewards?

No idea, but maybe there's something useful in this thread: https://www.steamgifts.com/discussion/QH43o/can-i-give-away-amd-reward-games

I guess, but you'd be putting a LOT of faith in the winner, and you'd only be able to do it the one time since you can't unlink accounts.

I mean I think people like me are down to do that, but I feel the best would be to invite people to a private giveaway based on them being ok with it to begin with :)

You could probably do that but only in some small group GA, i wouldn't put much trust in the people that usually enter public GAs :p

I would only consider doing that with a private group or whitelist where everyone agrees with it before hand.

as mentioned below this is something you won't be able to unlink and I wouldn't recommend doing anything that isn't a key/humble gift url or steam gift giveaway.

also make sure AMD isn't doing a hardware check for the hardware that game is supposed to be bundled with.

Short answer - eek. I wouldn't go there.

must be more efficient try it with a friend, or as others said with a small trusty group

Without reading the site rules I would say no, since the site asks for a Key or Steam gift. If you're referring to make an outside giveaway without any CV here then sure. All the AMD login sounds like a mess.