@David2025 Yes, your situation was completely different, the only similarity being that a host was asking a guest to pay for damages. In your case, as is obvious from the photos you posted, and to anyone who knows anything about construction, those stairs were funky and a disaster waiting to happen. Unless you weigh 400 pounds and were jumping up and down on the stairs with the intention to break them, there is no way a thick board like that can break unless it is defective, or not supported properly.
@Jocy0 appears to have completely disregarded the host's house rules, caused negligent damages, and walked away from the house ignoring check-out instructions and leaving the place unlocked and open to theft. Then refuses to take responsibility for her behavior, which isn't surprising from someone who behaves like that in the first place.
I'm glad you answered her post.