It was in the open air, with all documents carved onto rocks in some derivative of proto Mayan. This isn’t Patagonian, this is one of the other proto Mayan written languages. There are about 30 still in existence, but there were many more before. Proto Mayan is a big language family, just like proto Indo European is responsible for most of the European languages.
But yeah, the library was in the open air, with the mirrored spheres winched up, hanging over the effectively open books, so any script could be seen and consulted from anywhere with a mirrored sphere, anywhere in Patagonia.