That seems very suspicious to me. I don’t know how anyone would be able to do so as Crown items become bound upon acquisition, to you or the person you’re gifting them to. Maybe there is a way to keep items somehow in limbo and unbound? Those prices are pretty outrageous so, if it’s legit, I guess you’d be paying for that.

What probably happened is they gifted these items to someone who returned them, or simply didn't collect them. When that happens the gift is returned to the sender but they can't claim it themselves and can't get a refund, all they can do is gift it to someone else.

The worst that could have happened is they did that deliberately by gifting these items to their own second account then letting the offer expire so they'd be returned and available to re-gift after they were out of the crown store, but even then it's not against the TOS or even particlarly suspicious, it's still just using the system as ZOS designed it. The worst it would mean is the buyer is less likely to be able to negotiate a good price because the seller is aiming to make a profit rather than get rid of some useless items.