Received this info today. Pubblished: Hunting Report - 23 July 2015
A Delta Airlines gate agent has denied boarding to a hunter traveling to South Africa for not having a firearm import permit with him. The agent insisted that the South African Police Service (SAPS) requires travellers to have an import permit issued to them 21 days prior to travel. This is incorrect, and hunters traveling with Delta need to be prepared with paperwork and information to counter this.

Forget the paper work, change your flights to another airline.

As a business owner I sometimes have employees do things that defy logic, this could easily be one of those cases as it seems to be an isolated incident.
I have personally never had any problems with Delta & will not judge an entire company because of some idiot that works for them.
Now the denying to transport trophy shipments is a company policy issue & I do take offense to that.