I'm going to have to go back and read through these pages, but from what I'm reading through the interactions between Nem/Mikey so far seems to feel more like a scum vs. town interaction.

If Mikey is indeed Mafia, then claiming Miller/Thief isn't a bad hand as a townsided Miller in any game should be outing immediately in their first post of the game to prevent any possible mafia member CC's. Since no one did in fact claim Miller day 1 this isn't a bad move on his part entirely. (WIFOM)

If Mikey is actually town aligned Miller/Thief then he's one of our investigative sources within the game. Which is another safe tactic for Mafia to use. (WIFOM)

I'll finish reading this afternoon and post again with the Nemesis analyzation.