We are having a problem with some similarities, but only on phone, specifically iPhone 6S: error message when clicking on any photo on photo stack in IRIS while on an iPhones using latest updates. Some say this happens after updating to iOS 10.
Does not happen for us on desktop.
Happens using Safari and Chrome on iPhone, but not some other browsers, for instance, Dolphin.
We are not having the other issues you are having: wrong photo opening, and so on.
Advice on this earlier thread was to reduce the number of images. I tested that and it does seem to work. Hardly ideal, I know.