The Image collection layer configuration is a Dynamic Imagery layer, which can maintain the attribute table. However, for out of organization sharing, only Tiled Imagery layers will work for that. I am just curious about your workflow and type of images. From your previous description, I wasn't sure if you had aerial images or since you said user submitted, it made me think that they were pictures. Perhaps if you explained what types of images you had, then I could make a recommendation.