I found an outfit called Mogambo Tours in Lanseria, South Africa, and wrote to them to ask how they got their name. A kind fellow named Eric YVER de la BRUCHOLLERIE wrote back to say: "In 1996, we took over a company called AIR MOGAMBO and renamed it as MOGAMBO TOURS. I believe the previous owner did derive the name from the 1953 movie starring Eva Gardner." Rats! Another dead end street.