re: Advice on wall repair

You could just cover the hole with plywood on the outside and put some fake shutters over it and close up the wall on the inside.  On my garden shed I found an old salvaged wooden window, painted it and just hung it on an outside wall to dress up the shed. I also put a flower box below it. You can paint the inside of the glass black or add some reflective film to hide the fact that it is a fake window.