@Karen1119 I am sorry that this has happened to you, and it is so heartbreaking when your beautiful efforts are ruined by a guest. You may wish to apply to your homeowners insurance and give them the information about the guest who caused the damage if the repair is that expensive.
I have had guests cut on my countertops too. My solution was to buy a huge, heavy, oversized cutting board that was left out on the countertop in PLAIN SIGHT and was almost too large to move and could not be tucked into a cupboard. Good luck!