I'll be quite honest, I don't think this episode is so special. Sesame has thousands of episodes that they haven't officially released. I'm sure this episode is stored away in the vault just like all the others. I don't think this episode is being hidden from the public, I just think SW has other concerns than releasing this one episode, just like they don't seem to be interested in releasing most of the older episodes. We have no reason to believe this episode or any other episode was deleted. We know that this episode was never re-aired because it didn't work, but I don't think this is the only episode that didn't re-air. Back in the day, the show had so many episodes in each season, that they probably couldn't have rerun a majority of them. In fact, it's been said that that's the reason the show used to have so many episodes, it was because they were not meant to be re-run in the first place.