When a non-Admin user takes a survey in the Survey123 for ArcGIS field app that was created from the Survey123 for ArcGIS website and they include a photo attachment, the survey successfully submits but the feature is not created in ArcGIS Online.
Double-click the new Survey to open it, and choose Publish. This creates an identical, new survey in your organization.
Share this survey and hosted feature service with the organization, or publicly. With this new survey and hosted feature service, publishers are able to send survey submissions with photos as expected. This is verified by examining the hosted feature service: https://petey.maps.arcgis.com/home/item.html?id=b3543751a9a5491cbc9aa7a7288cc527