The Muppet Wiki page for Suzanne Farrell includes video links to all of her appearances. Which includes this rarity, "At the Barre".
I'd seen on Scott's page that one script with the sketch lists Herry and Telly while another lists Grover and Herry. When I first saw the segment described in an episode page, it said that it had Grover, Herry, and another monster, which made me suspect that it was Telly, during the transitional period where he was a generic monster. And I was right that Telly was in it, only it turns out Grover wasn't, while the monster that was once called Kermit the Gorf does show up. I guess they decided to replace Grover with one of those two monsters. I wonder if it's because they eat the barre (I don't think Grover has ever eaten anything ineible, but I have seen Herry do so on rare occasions).
And since it was made before Brian Meehl started doing Telly as a character (well, I assume; by episode number, it's before Telly became an actual character, I wonder if the taping dates have the same chronology), I was surprised to see that Meehl performed Telly here as well. Meehl uses a similar voice to the one he would give Telly, only with a French accent. Back when I speculated that the sketch had Telly, Grover, and Herry, I assumed Jim Henson performed him here (since he performed Kermit alongside Farrell in other sketches, I thought they were all taped on the same day, and therefore knew Jim Henson would be on set), though I can't really tell who is performing Kermit the Gorf (I want to say that's a Michael Earl voice, but he doesn't get much dialogue). It's also interesting, at this point Herry is the most recognizable monster in the bit, but Telly is the one to get most of the dialogue.