Just got a PM from Masato who says:

"I've checked several indexes of songs, spirituals, gospel, and folktales, but unfortunately no information on this song has been
found so far, at least under this (including "All the Gold in the Mountain") or similar titles. I'll continue keeping watch."

Well, now the search is getting serious, and even more interesting. It could be that this song came from the "minstrel shows" rather than the Black Gospel tradition. Wish we knew more about the range of songs Ella sang in the musical groups she was active with in the late 19th century.

Charley Noble