We might be sewed

Sounds to me like the board member who did the book just wants to fight. That's silly. As was mentioned by someone else, I would suggest sitting down together (with lawyers if you want) and find out exactly what the complaint(s) is. No matter what, it's not possible you have copyrighted her book. She probably means you copied her book. She may be under the impression that because she published a book she has rights. She doesn't automatically have any rights. She would have had to go through a process to get a copyright. If she didn't get a copyright on it, anybody (including you) can make copies. But in the long run, if you don't make any money on the books, why get lawyers to find out what rights everybody has? Just stop selling the books or destroy them.

I think both parties should sit down and talk and see where the violation of copyrights existed. Preferably with the experts present. Then if it is indeed proven that the museum is in the wrong, then might as well destroy the books. No sense in spending more for something that isn't rightfully theirs to claim and that brings in little money at that.

I have to say that I definitely agree with you that your board should just destroy the books that you've already had printed as opposed to going through a long and drawn out legal battle that will also end up being something that is very expensive. The fact is the money that would be spent on the legal battle is money that would be better spent elsewhere for exhibits or maintenance of the museum. To lose all of that money would hurt people not only today but in the future as well.

I think you should get all, you information, about the book first, and if it's true the book have been coped, then I think destroying the book,would be doing the right thing, because it will be a lot of trouble, selling some thing this museum, didn't published in the first place.