How to add invisible paint layer to vertex painting material?

Hi, I’m trying to create the hole in the ceiling

shown in the reference image using the vertex painting method. The problem is that my blueprint of my material is not letting me paint on the rusted metal texture and the invisible texture. I have followed the official unreal engine vertex painting tutorial on 3 way painting but is not working and does not tell me how to paint clear textures onto a basic floor block. Here are the blueprints…

34846-vertex+painting+ss.png

34849-vertex+painting+ss.png

clearer picture of blueprints screenshot