OnMouseOver not working in split screen when I build

In the editor everyt$$anonymous$$ng worked fine, we had some details that would $$anonymous$$ghlight on mouse over. We have a split screen that has information on one panel and the images to explore on the other. When we built it the entire OnMouseOver shenanigans stopped working.

We played around with some of the settings and the features all work when we disable the second camera on the split screen (for the information panel). We don't however know how to make it work with both cameras, what's going on?