What does your boss expect if you can't show the face of the person being interviewed??? Either you throw their face into a black shadow, or you only shoot the back of their heads, or only body parts like hands, something expressive. But if you are going to point the camera at their face and you aren't supposed to see who it is, then you're talking about keeping the light off of them so they go black.
I remember this old comedy sketch on TV, maybe it was SCTV or Benny Hill, where the TV show host / interviewer was talking to a man under a death threat from the Mob... but accidentally sat in the chair that was unlit / silhouette and the subject sat in the bright spotlight, confused and nervous -- by the time the interviewer realized that this was backwards and switched seats, the person being interviewed was shot by a sniper...
