A ferry flight with a spare seat
An empty leg is a repositioning flight an operator would fly anyway. Selling the seats is better than flying them empty, so the price is often below a retail charter of the same cabin. It is also brittle. If the owner trip that caused the ferry is cancelled, the empty leg goes with it.
The date, the aircraft type, and the city pair on a Vinto card come from the Limitless Sky feed. The operator named in the specs is the carrier. Vinto does not dispatch the airplane.
The credit link is a license term
Limitless Sky publishes the feed for free if each item carries a normal, crawlable link back. Not nofollow, not a cloaked redirect. You will see that link on every empty-leg page, worded as a credit. If Vinto later has a paid relationship with them, that label has to be renegotiated. It is not an affiliate badge today.
A request form on the same page can ask an independent charter desk to look at the route. That is a separate conversation. The live offer is the one on the credit link.
Read the price as perishable
A dollar figure was the operator's asking price when the feed was read. It can be gone by the afternoon. 'Price on request' means the feed did not publish a number. Neither phrase is a Vinto fare.