Someone on another site said they'd heard about a museum that contained 40,000 ancient documents that was destroyed, but that was all the information they had. Most likely, if this is true, it was a mini-museum in a public library, or synagogue. Plus, unless it was one of the first buildings destroyed, the docents and employees would have done all they could to remove items ahead of time.
My town has too many businesspeople who insist in building in a riverside flood plain that literally goes over the banks every year, and when the Hesco-barrier levee broke in 2019, causing record flooding, when it looked like things were about to go sideways, a record store enlisted the community to empty the building, and a small museum a block or two away, that was in a basement, also did the same thing. The record store relocated in a nearby building that was about 10 feet higher, and the museum was able to reopen in the same space. (not a good idea)