An extremely unwelcome guest entered the house another way than the photo shows but had the nerve to wreak havoc on both plaster, vapor barrier, and insulation from the kitchen side of the wall. Reaching the corner under the kitchen counter and cabinets requires lying flat along the floor and having at least 150cm arm length for each arm, which is obviously not possible. How the heck are you supposed to both insulate and install some type of board/replacement wall structure?