This was probably no accident. The show in question was created during the few years that series creator Lorne Michaels was estranged from the show, and the notoriously controlling producer has induced an institutional amnesia when it comes to that period. There's also the fact that it's one of the few brief moments in SNL history where the people nominally running the show had absolutely zero control over what was going on in front of their cameras, and the results included a minor onstage riot and a follow-up meeting between then producer Dick Ebersol and the presumably very unhappy NBC president, Grant Tinker.
But a complete, uncut copy of the performance, with all of the swears and collective gasps of the studio audience—and by extension the entire nation of SNL viewers—intact, has been on YouTube since August, although a tweet about it by Chunklet founder Henry Owings just brought it to a lot of rock nerds' attention on Friday.
For a brief overview of how John Belushi basically blackmailed Ebersol into booking the band, check out Jake Fogelnest's blog post about it.