Images and Text Boxes Disappearing, Files Still Linked

Hi there! I was working on a catalog file that's been rolling around with no issues when all of a sudden I scrolled to a new spread and 90% of the images and text blocks on the page vanished like they'd been hidden. As far as I can tell they haven't been (at least not by any keystroke I've made or any other toggle.) I've tried toggling presentation mode and preview mode to no avail. Even stranger still, the only pages that seem affected are between 28 and 33, roughly the center of our document.

The images and text blocks that survived the mysterious disappearing act are un-selectable, as if locked on a master page (though checking the masters reveals nothing amiss, nor does clicking to unlock them as if they were a master asset do anything).

The strange thing is that all the linked images are still "present" on the page and I can see them in the links panel. Cutting and copying some of them to the affected pages fixed it for a moment, but on save + reload made it worse... I've tried resetting my preferences and saving the file under a new name, but nothing is working. I'm at my wit's end and any help is appreciated!

(Note: this happened before updating to v 16.1. I updated the program after noticing the error and as far as I can tell this made it worse...)