This black Lord is called Musse Melly and is the sovereign of the land of the negroes of Gineva [Ghana]. This king is the richest and noblest of all these lands due to the abundance of gold that is extracted from his lands.
This Musse Melly is really close to the description to the Mansa Musa. Even though they have different names, I feel like the text is refering to the same person. By looks of the description, they seem very similar.
Cape Finisterre [end of the land] of Occidental Africa. Here starts Africa, which ends in Alexandria and Babylon; it starts here and encompasses all the Barbarian Coast extending towards Alexandria, towards the south, and towards Ethiopia; in these regions, there is a lot of ivory due to plenty of elephants (...)
I feel like this text is close related to the Mansa Munsa. In ethiopedia, many muslim religion closely associated themselves with the Mansa Musa king. Then the writing associated with this document is arabic