Homer's Brazilian Kidnappers are the criminals that took Homer hostage while on a short-lived holiday to Brazil to find a missing orphan that Lisa was sponsoring, whose name was Ronaldo.
Details of the Kidnapping
Kidnapper #1: The first kidnapper was the one who took Homer hostage in an unlicensed taxi at gunpoint. It said in Lisa's book not to get into an unlicensed taxi, but Homer paid no attention whatsoever to what she was saying. The kidnapper had a brown mustache and a deep Brazilian accent. He seemed to be more concerned about Homer than the other kidnapper.
Kidnapper #2: The second kidnapper that took Homer hostage was not in the taxi that the first kidnapper was driving but appeared later in the episode, driving a speedboat along the Amazon river. He told Homer to get a bag off his head that smelled of cinnamon. He said, 'Behold the Amazon river, but quick, because we are burning it down.' He tricked both kidnappers to go to the toilet in the bushes. He said that he had a bladder the size of a nut, and with this they let him go into the bushes. He said suckers while running through a bat cave, and then said bloodsuckers.
He ran back to the boat, where he was held hostage again.