Two versions of the Dudley Moore episode?

[DMHFan]

There's something that puzzles me: Why were two versions of the Dudley Moore episode of The Muppet Show with alterations in the end credits music, one where before Statler and Waldorf's closing comment, part of the Season 3-4 version of the show's closing theme can be heard, and another where before said comment, the music that played in the UK spot can be heard?

Versions for context:

P.S. If it helps, try comparing the two versions of the shot where Animal bumps into M.A.M.M.A. and find out how different the music/sound is between the two versions.