This is going to drive me crazy. In the SNL sketch there's a clip of a cartoon with a car that looks like a penis. I seem to remember that Sweet linked to that clip in one of his posts, either here or on AJM. Can't seem to find it, though.
Is the penis car clip quite well-known? Has it become a meme or something? Assuming Sweet did link it, is it likely he discovered it somewhere other than the SNL sketch?
Putting aside the penis car clip; on the basis of available evidence, the draft sketch Sweet wrote shows no obvious signs of ripping off the SNL sketch. When he does copy from other works, he's not exactly subtle - ALFichu, Harley Quinn, catchphrases like "when does the hurting stop?". He's also incredibly immature - there's no way that the vomit jokes or the "shots of a fat man's ass" from the SNL sketch wouldn't have made their way into his sketch in some thinly-disguisedH form.
He's racist, and Rush Limbaugh might have a claim for gimmick infringement, but I'm unconvinced that he plagiarised the SNL sketch. I do think it's likely that his exceptional reaction to the accusations got him permabanned when taken in conjunction with his record of screaming at his colleagues and weirding them out.