Mesilim
Mesilim (Sumerian: 𒈨𒁲),[3] also spelled Mesalim (c. 2600 BC), was lugal (king) of the Sumerian city-state of Kish.
Though his name is missing from the Sumerian king list, Mesilim is among the earliest historical figures recorded in archaeological documents. He reigned some time in the "Early Dynastic III" period (c. 2500–2330 BC). Inscriptions from his reign state that he sponsored temple constructions in both Adab and Lagash, where he apparently enjoyed some suzerainty.[4] He is also known from a number of fragments
Moses
Summary
So Moses is connected to Cush/Kush.
And there was a factual historical and archaeological king of Kish from Mesopotamia in 2600bc, named Mesilim. He is not in historical records, however arachaeological excavations have found that the kingship of Kish pre-dates historical records, and that the first king of Kish was likely Mesilim.
I can find nowhere however, archaeologists nor historians making the connection between the kingdom of Kish, and Kingdom of Kush