The giftcards are not purchased with a credit card. They are not fraudulent in any way, shape or form.
This can't be proven so it isn't much of an assurance. Not saying you are running a scam but the last 20 or so scammers selling gift cards were equally adamant about how safe and legit they were.
Just to plays devils advocate what would you expect a scammer to say? "dude this is totally risky and not really a good deal and I am unwilling to use a middleman or escrow want some giftcards?"