Was just wondering if a former follower of the Chosen One will stay in the place that you left him in (out of my party and won't rejoin until I gain more charisma) for an extended period of time? I need to leave Vic until I can gain a couple of levels and get the Magnetic Personality perk, will he still be there in a week or more?

By my knowledge, as long as you leave him in a town or other location (as in not a random or special encounter location), like Redding or Vault City for example, he will remain there forever until you pick him up again.

Yeah, just don't leave him stranded in the middle of the wasteland