I can neither deny or confirm

I always thought it was Andy, not Toby. Andy was just a little too unhinged. Here's a reddit post with assloads of rather convincing evidence: https://www.reddit.com/r/DunderMifflin/comments/5mvak0/andy_bernard_has_disassociative_identity_disorder/?utm_source=amp&utm_medium=&utm_content=post_body

I can't choose between Hannibal and Dexter.