As you know DC Ron Rivera is under contract for another 2 weeks. In general a team will only give another team permission to talk to their coordinators if it is about a head coaching position.
His theory then is he says he is interviewing Rivera for the head coaching job, but then in the interview can try to see his interest in being the DC in the big D.
First off, if this is true then FU! Jerry. How about a little friggin class around here? If Rivera wants to go to Dallas because he wants to improve his chances of becoming a head coach then fine. All he has to do is not resign with the Bears. No need for underhandedness. Just play it straight. You really don't have any competition for him right now.
Secondly, as the article points out it seems odd that you have been drafting and signing people to run the 3-4 and you are going after a DC that runs the Cover/Tampa-2? I don't believe you have the linebackers for that among other things.