You would call someone "garbongo" when they are clearly wrong.
Garbongo means that something or someone are lower then trash and deserves to be burned like the filthy garbage they are
A bumbling lump, knuckle dragger, buffoon, or chucklehead, meant as a combination of garbage, bozo and gorilla, a concise way of calling somebody a big dumbass.
Garboza: Ahh, sorry boss, I busted another chair...
Boss: You god damn garboza you, that's the third time, should I get you a crane instead? Lay off the fried chicken!