I forget if the story is recorded in the book of Enoch or in the Assumption of Moses. For more detail look for a book online called legends of the Jews.
In short, the Jewish people worshipped many false gods, like the golden calf for example. The concern with hidding Moses body, was to keep satan from tempting the Jewish people into worshipping it as an idol.
Josephus records that Moses was assumed into heaven.
Other Jewish sources, support the claim that Moses really died and was resurrected.
Since, Moses murdered a man, Satan would be making a leagal claim to Moses for that sin.