I think you can still do it. If you look at the 2nd picture I posted above, you'll see that the fp is actually recessed into the surrounding bookshelves. So you can make the shelves on the right side, say (sorry I don't know metric) 10" deep and the ones on the right 18" deep. The fronts will line up and look even. You'd want something deeper where the tv and components go anyway as they tend to be deeper and need more air circulation to dissipate heat. You'd just have to watch code in your area for how close combustible materials can be to the fire box. Most likely this would need to be done custom. I know fireplaces look very permanent, but one thing I've learned in my years of looking at remodels is, there's a boat load more flexibility in fireplace surrounds than you think. More examples of recessed fireplaces:

It would help if we had a better idea about the orientation of the rooms -- the space you have available. I agree with those who suggested you consider swapping the functions of the rooms -- make the existing dining room the TV viewing room and move the DR table to another room (LR or FR). Failing that, is it possible to extend the feed from the security cameras to a location where you would actually want to sit and watch TV? Failing that, could you purchase a nice tablet for hubby that he can have with him anywhere in the house, so he would have ready access to view the security feeds? After all, I would think the need to view those feeds is momentary at best -- watch a movie, pause the movie to check cameras for a second, return to movie -- right? He's not going to actually sit there and watch the feeds for any appreciable period of time, I would think (although my father can sit for appreciable periods of time watching the Weather Channel, so what do I know?).

Would you be able to upload / post photos here, in these comments....

So my very first thought. The room is of balance. The light fixture in this case needs the weight of the furniture centered to it. I would move the couch over. That window also deserves more presence. The stove seems more of a plant stand so I wouldn’t make it stand alone. Then wall mount the tv stick with the scandy feel you have going for tv stand. Use art as the color and interest