This is a brick wood-burning fireplace, original to the home built in the 1980s. I am trying to get all the small drilled holes emptied and filled.

What are these 4 screws for? There is one small screw above and below the pieces of blue tape on each side of the fireplace. The bottom 2 screws are about 7 inches above the fireplace opening, and the other 2 are 3-4” directly above the bottom two screws. I think I caught a pic of some metal inside the fireplace. Could these screws be necessary to attach that metal flue (or whatever it is) inside the fireplace? Or do you think it’s safe to remove them?