Fake HDR on Interview?

Luma key might not be the best option. Rotobrush is slow and should only really be used on short shots. 

If you can post a frame from a couple of the interviews without any color correction, I could give you some better suggestions for creating a suitable track matte. The white hair on the subject and the light background might cause a problem, but some color correction and fiddling may get you there with less trouble than just trying a single Luma Key solution. You are also going to need to add masks for the window frame. You will not find a one mask, one effect, solution, and the masking is going to require some keyframing unless the subject or camera doesn't move at all. 

In the future, try dragging your images to the Reply field instead of using the Attach button. It makes them a lot easier to see.

Well, you could have saved yourself the trouble by shooting against a green screen. If you have a clean plate of the window, you can try a difference key and/ or generating procedural mattes using channel operations to cut stuff out, but otherwise you're facing loots of work. The sky is as white as the highlights on the face and the window beams are as black as the shirt. See the problem? You'll still have to do quite a bit of masking even if you can generate mattes, at least where the guy and the background intersect. Hard to tell what might work without at least images of the clean plates to check what might work by loading them in AE and dabbling with effects...

Mylenium