if paypal is used as method of payment, you can file a dispute against the one who scammed you but as internally as far as domain registrars are concerned, there are no domain ownership change, all pushes and transfer happened internally and they can't stand as referree if a domain pushes over to another domainer without their knowledge and without payment, i think there's weakness in that kind of policy on that area, where domainers are really left on their own.
