I have heard of known-shipper status but since Delta has not allowed reptiles to be shipped by their "Pets First" method I do not know why you would need to be a known shipper. Pets first is reserved for dogs and cats and I think birds. Not "lower" forms of life like reptiles. They used to do it but not anymore.

If I need to ship something I just call Delta Dash and tell them I need a package shipped and schedule the flight. I just drive the box to the airport and they take it. Be aware that no shipper guarantees live animal delivery. Even Delta Dash only guarantees that the package will get there. They have insurance but it does not apply to the animal being alive upon arrival. If the package is lost for ever you can get money. Of course, 2 weeks later and they will send it to you and just refund your shipping fee.