Hey,

You shouldn't need to pay to return it to sender. I work for a different games company and in cases where we can't cancel pre-orders and people need to return them to us for a refund, we tell them to refuse the delivery. The postman will update the tracker to show the delivery was refused and it will make its way back to the senders address. As soon as it has been refused, you should be able to contact them again with your tracking number, let them know its been refused and they should be able to see this too and issue the refund straight away.