I have this damage to my external walls render. I backfilled it with spray foam (which is currently curing). I was going to fix it using Dunlop Joint & Patch Render which I had purchased, but I'm wondering if it's the wrong thing to use, because it looks very smooth, but my existing render is very textured as you can see in the photo, which seems to have large grains in it. What products should I use to fix this, and how? Thanks.