Hes a DB coach. Not a head coach or coordinator. Them being 3-9 has nothing to do with him.
I disagree with your premise (that positions coaches have nothing to do with record), but agree that he's not responsible for 3-9, if for no other reason than he was only hired to Arizona this year.
But there is something to be said in that he's never been part of a winning culture, as far as I can tell. San Jose St was terrible while he was there, for example.
In the end, he's being hired because he's supposed to be a great recruiter - will be interesting to see if he can pull kids to NU as well as he seems to have pulled to Arizona during a partial recruiting cycle.
I find it interesting that some here are not eviscerating him for lasting less than a year at Arizona - essentially bailing on his commitment there. Personally, I have not much problems with a coach jumping, especially if the players/recruits are able to bail, too, if needed.