Google My Business has updated the photo views Insights report to let you filter the images based on if the owner uploaded the photo or a customer uploaded the photo. There is a new drop down to filter by (a) all photos, (b) owner photos and (c) customer photos.
Here is a screen shot displaying this new filter:
Andy Simpson I think was one of the first to spot this and he posted about it on Twitter. He said "Now you can see who's photo gets the most views in GMB dashboard." I noticed this filter back in September 2020 but I don't think many people know about this filter option.
Forum discussion at Twitter.