There's an album called "The Underground EP" from I think right after Eminem made Infinite. It's old as dirt, and I don't even think Em was an official member back then because this was made with Bugs still alive. Anyway, it's like a 10 song EP and Em is on at least 5 songs. So Em does know these guys from way back, but yeah, keep reaching.
Besides, even if the "band" was made up, Eminems putting a million or 2 in strangers pockets, so what's the big whop? But that's neither hear nor there because they go way back.