You have used "user story maps" but also mentioned "user journey." Story mapping and journey mapping, though they look similar, have different purposes. You might wsant to check out this article which discusses the difference: https://www.nngroup.com/articles/user-story-mapping/#:~:text=User%2DStory%20Mapping%20vs.&text=A%20customer%2Djourney%20map%20takes,the%20perspective%20of%20the%20product.

Also, if you are going to discuss story mapping, I feel you should give credit to the person most notable for promoting this approach, Jeff Patton (https://www.jpattonassociates.com/story-mapping/) who introduced the concept in 2005 though it was not named "user story mapping" until 2008.