Just to be clear, the TSA and other "security" cock gobblers are authorized and equipped to get in to any case they want in.
A few years ago, I got separated from my guns and they stayed in Chicago while I went on to Namibia via Swiss Air. When the gun case showed up, eventually, TSA had cut my Masterlocks and left a note. They then re-attached one of the extra locks I had packed inside the case. Swiss Air, or whoever, then opened the case again (another note!) and sent the case on to JHB secured with the other extra lock I had. I'm not sure what happened in South Africa, but when the case showed up in Windhoek it had one lock, with the wrong key jammed into it so solid it took pliers and a hammer to get out, and a wire tie! Everyone did return my locks, jagged bolt cut pieces and all, rattling around in the case with the guns!
The rifles were fine, but I had to buy new locks in Windhoek before returning!
