It's been awhile since I read the book How did Fredo react to being stepped over for Donship by his kid brother? Thanks Pete
Fredo v. Michael isn't really an issue in the book. "Freddy" seems contented in Vegas, running the hotel side of Moe's operation and chasing cocktail waitresses. There is the "don't take sides" confrontation, but that's more that Freddy is identifying with Moe than with Freddy asserting some kind of authority among the Corleones.
Also "Fredo will run the five or so Corleone hotels" but under Boss Michael though
Well, sure, that's where the money's coming from. Same as the people who actually worked for the olive oil company.