Regardless of the camera I use - GOS CAM, Google CAM…

You have to leave the camera app and select the gallery app to view photos. (due to the camera wanting to use google photos?, and no google photos on my phone)..

Minor issue - but is there a way to set the camera apps to default to the gallery app from the camera?

The GOS camera app opens Simple Gallery Pro on my phone without having to exit the app and all that nonsense. The first time I did this it asked me which gallery app I wanted to use. I just tapped always use Simple Gallery Pro and it has worked since.

However, Google's camera app always whines that I don't have Google Photos installed. I'm sure that's how they set it up because Google is evil and wants everyone stuck in their ecosystem.

    unwat When I try that - I get ""Captured Photos/Videos Not Found"

    I was able to recreate your problem and got the same error message and I think I have an explanation but no real solution.

    The camera app has no access to device storage, but any app can save certain kinds of files to corresponding folders, i.e. a camera app can save photos to the photos folder but can only access files it creates. So, the GOS camera wouldn't be able to open Google Camera photos, for example. If you use GOS Camera app to take photos you should be able to see the recent photos there. If you want to see photos from both apps, it's better to just use the gallery app since it should have access to file storage.

    If you've already been using GOS Camera and it's throwing that error message then I have no explanation.