The Biggest Douche in the Universe - S6-E15
Continuity mistake: When Stan goes to see John Edwards, John Edwards's butler goes to get him. When the butler reappears (just before he pushes the buttons on the wall for the recorded voices), he reappears from the right of the archway. But John Edwards appears from the left of the archway when the voices are playing.
The Biggest Douche in the Universe - S6-E15
Other mistake: When the trailer for 'Kenny' is being shown, the label on the pot roast has McGilroy written on it, instead of McElroy (which is Chef's actual surname).
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
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