3) Reid Ryan Allen. The original suspect in the murders/disappearances of all 22 girls and the death of Alex Hartley.
Brandon may or may not have killed Loren; as of now Allen is still the only official suspect in her murder. There is no proof that Brandon killed Alex Hartley, Brandon simply videotaped the crime scene. There is also no proof that Brandon even killed Allen. There's no proof that Brandon killed anybody, actually, and nobody has any clue who Brandon really is. There is also no proof that the other 21 missing girls, despite 18 of them being identified and 17 of them being shown "murdered" on camera, are even dead.
So, really, there's nothing that can prove the most infamous serial killer who ever lived is even, in fact, a killer at all.