If you're refering to the bald guy in the pool during the #8 segment... Then sorry, but I have no info on that character's name or actor's real name.
Maybe in a few years if my Muppet List finally gets off the ground and becomes the Muppet Universe I envision it becoming...
Maybe someone else can help though, someone with onstage contacts like Secret Squirrel? Or maybe someone with infinitely more knowledge than I like GB.
Hope this helps.