I had a landlord once who gave me an enormous folder of datestamped photos and made me sign a statement that they were a true and accurate record when I moved in.
Came in handy when I moved out and they tried to get me to pay for the crack in a window pane that was clearly visible in several of their own photos.
Spiders work fast. They rebuild webs in a matter of hours. It's not a realistic demand.
Though at the time the amount they wanted was not worth the grief so I just moved on. But minor deposit frauds are extremely common and almost always unpunished. Landlords have essentially nothing to lose by trying it, certainly not morals.