Hi Daniel,
As long as you can embed the content in an iframe without any script tags you can embed it in a story map (Journal, Series, or Cascade). In Journal/Series you'd choose the "web page" option for your content and in Cascade you'd add the iframe code in the "Link to Content" tab of the Media Picker.
Can you post a sample of the embed code from the photo sphere here?
Owen
Owen Evans
Lead Product Engineer | StoryMaps