Pinball #5 was uploaded by Sesame Workshop.
It's the only pinball segment that was not available at sesamestreet.org (though it, along with the rest, was a bonus feature in Elmo's Magic Numbers and was included in episode 1257 which was part of Sesame Street Classics Vol. 1 so it's not like Sesame Workshop has avoided releasing this one in recent years).
But is it just me or has Sesame Workshop been choosing pinball segments the last few times they uploaded 1970s clips on their YouTube channel? It also seems like the last few 1980s clips posted have been Bert and Ernie clips.