Two things.
One, the story is already suspect since Lyfe has stated he was from and incarcerated in Ohio while Dahmer was from and incarcerated in Ohio.
Two, I'm pretty sure it was already established a while ago (maybe when he went to jail in the last 10 years) that his birth year of 1978 was bullshit so even his age would be off.
Essentially, I'm a fan of a lot of Lyfes music but I don't really put too much stock into the shit he says.