UFOs in concert with the Nazi’s blew Byrd’s planes out of the skies. He had no choice but to tuck tail and run.
Well, that’s one theory.
However given pictures of the Nazi logo on Bell shaped and saucer shaped stuff, there’s another theory that the Nazi’s had some bad a$$ military stuff - enough to defend their camp there.
Then there’s another theory regarding fallen angels or demons/other dimensional beings helping the Nazis there.
None of the theories are entirely satisfactory to me. I can wait to find out for a few more years.