I remember this!
From The Lost Media Wiki
I know I’m really late to the party (6 years late), and I may be remembering wrong, but I remember seeing this exact short on a House of Mouse DVD. It may not have been the full version of the short but I remember a scene with a coffin/chest that perfectly matches up with a scene in this short. I also remember that the short was about an extremely anxious Pluto, which is what this short is about. Too bad that I was young at the time of discovery and had no concept of “lost media”.