If you want to get a reluctant subject talking, the trick is to remove them from an environment that makes them feel uncomfortable.
Most people hate the traditional interview set up. It means they are being put in the spotlight (sometimes literally) with all eyes on them (and they would be right on that fact). So give the traditional corporate video a different look and remove them from that setting and put them in a different situation. Then the problem you will then have is getting them to stop talking!
James Cordon has recently perfected the art of the interview in the drivers seat. The environment is curiously intimate, yet the participants don’t even have to make eye contact (obviously it is better if the driver looks at the road!).
For the nervous subject, it means they can concentrate on something else while talking. Go-pros and smaller cameras mean it’s much easier to rig the car for both high quality sound and vision. The subject has to think about driving first and foremost, and so is not so fixated on what they are saying. It puts the emphasis on the producer to make sure all the agreed topics are covered, but the results are often much more revealing and spontaneous.