Amazon tracking issues

The Amazon system cannot track our freight shipments. We post tracking and carrier information to the orders. Seller Central says it recognizes this carrier for tracking. Amazon then sends the buyers emails saying the shipment is late and they can request a refund. The dishonest buyers file A to Z Claims against us claiming they did not receive the shipment. They signed for the delivery. The freight carrier uses GPS on the trucks, they get a signature, and often take photos of the delivery location. Amazon doesn't allow us to attach any of this information to our A to Z appeal, but we tell them it is available. They give the buyer a full refund and he/she gets to keep a $1500 to $2500 order that cost us hundreds of dollars to ship. Why can't we get an agent to look at appeals that will actually read the information we provide? Amazon is costing sellers thousands of dollars while allowing customers to steal. Is there any recourse after an appeal is denied?