Hover-state for 1 icon won't work with camera

The hover state for 1 icon isn't working (the white book icon inside the paintings). I've traced the problem back to the camera (once removed, it works fine), but I need the camera for the zoom feature. After removing the camera and re-implementing it, I was able to get the colored book icons to work, but the white one is still being stubborn. I've tried redoing the icon starting completely from scratch, changed/deleted/added layers, changed the order in which I set up the icon/hover/camera/etc, nothing works. Hoping someone can help, at this point it's just driving me batty.

(to see the white book icon, click on a painting, then click the "info" icon on the right)

(edited)

https://drive.google.com/file/d/1oWK33BC3EueFvBXSmn4ByR-NpCQ-63xl/view?usp=sharing