Good lord, Rig! That is tragic.

Chongo's surname is Chimp. He adopted that surname for legal reasons upon entering the USA. He had just been called "Chongo" before that when he lived in Africa. Bush chimps don't have surnames, just given names. Most American primates really prefer to go simply by a given name, but the human bureaucracy won't provide them with papers unless they adopt a surname, so Chongo went for the obvious and took the surname "Chimp".