Glad to hear Simon is getting better.
It never fails to amaze me that, considering what finnicky eaters they are, they WON'T eat their food but they will eat rugs, toys, shoes, etc.
Our first Yorkie was still a baby when we moved to our current home. We had wallpapered the kitchen with material instead of wallpaper (it was the 80s) and we had a thin piece of trim at the bottom, right atop the existing floorboard. Scruffy managed to find one tiny piece of material and pulled it across the wall, eventually yanking several inches off in strips. Not sure how much of it he ate. He washed it down with a healthy serving of the small piece of trim (2-3 inches worth) at the bottom, the little termite.
That was a scary trip to the vet ... but he lived for nearly 11 more years after that.