I am thankful to live in a world where a character from the Illuminatus! trilogy can pop up in a rather funny Muppets video. The show that it appears in on aired in 1980, so in theory Wilson or Shea or both could have seen. it.
Hat tip, Jesse Walker.
UPDATE: On Twitter, Jesse remarks, "The Muppet Show was made in the U.K., and I think there was a little bit of overlap between its staff and the Ken Campbell crowd."