Hi, Grant! Just got back online last night. There *is* video of the Murgatroyd character, but I don't own the disc it was on. I know it wasn't YouTube but one of the DVD releases (I think *not* the ones with the obnoxious CG superimposed additions, I avoided that for Wiki research purposes). If I can figure out which specific disc or set, I'll let you know. I don't know if this was the only appearance of the character or not (I was mostly keeping an eye out for Spinney's on-camera roles like Grandma Nellie, and found out the kangaroo also showed part of his face, but in the meantime found myself of course noting other suit or puppet roles in passing, and this caught my attention, a step above what they usually had on the show; the fact they only had four supporting cast members at any one time plus Bozo and a very small space made it an inherently cheaper and smaller looking circus compared to the generally better regarded Chicago version, which wasn't what Larry Harmon chose to have syndicated though).
Not sure which episode, but it's in that set somewhere. I'm not sure I got through every episode. It's not always easy watching, in part because unlike Sesame and Muppets, it was purely pitched at kids and heavily at the peanut gallery present and so can be a bit raucous and just loud and lots of toy giveaways, but I can see how I would have loved it at age six say (I really grew up on the Bozo records, so I may also be biased). Outside of Paul Frees' voice, the cartoons are worse (at least you can see the live cast trying and, outside of Caroll, a pair of rather elderly old vaudevillians Ruth and Carl Carlson were quite game) but I know it had the one Murgatroyd bit. Caroll plays Grandma Nellie, Kookie (as you can see here, the eyes are visible within the mask), Mr. Lion (same thing, though I hadn't noticed at the time, but there's an online clip here; seems to be the same face paint as for Grandma, so he could just switch costumes easily), and the rest were mostly silent: Zany Zebra, a sort of Raggedy Andy type named Flip Flop (pretty much any puppet or suit character except the robot). I'm not sure there were any other straight puppet characters in that particular set, but checking, it looks like I only rented the first disc (so that narrows it further!)
And yeah, sometimes there are influences or one artist borrows from another, but (outside of say old comedy routines, where it usually was outright stealing, but everyone did it so pinpointing an originator is rare) in many cases it's just synchronicity (although I plan to write something soon about some showbiz influences on specific Muppet characters which aren't really as obvious, and already documented some on [[Lefty the Salesman], but as in most of the best cases, he's a composite, borrowing a few traits and catchphrases from two characters but the even breathier delivery and "Riiiight" were original, so the result stands up as characterization, compared to a pure ripoff). I think coincidental synchronicity is clearly the case here (similar enough that it's striking and startling, but also clearly different in purpose and some specifics; Murgatroyd is more slapsticky or plain novelty, eating a pie and so on).
Also, I like that video! (I could also imagine the character doing Louis Prima's "I Ain't Got Nobody.")