Great detective work. What a fascinating story! The only banjo I can think of at the moment that's definitely attributed to a performer is Fred Mather's banjo in the Smithsonian. Good job.
P. S. The pot does look like it might be a little newer than the neck, but that's not unusual for banjos of that era. I've got two of them myself. Just my own opinion, but I feel these banjos should all be made playable if feasible. Collectors may differ on this, but there's certainly enough meat on the bones there to make a great playing banjo.