As the developer, I'm able to GET (using PHP via the REST API) all notes from a notebook shared with a client. As you see, a search by me returns all 25 notes within the accessed section:
{ "@odata.context":"https://www.onenote.com/api/v1.0/$metadata#me/notes/sections('0-240BD74C83900C17%21128584')/pages(title,id,links,contentUrl)","@odata.count":25,"value":[ { ...
But logged in as my (duly authenticated) client (and using exactly the same code), we get 0 notes:
{ "@odata.context":"https://www.onenote.com/api/v1.0/$metadata#me/notes/sections('0-240BD74C83900C17%21128584')/pages(title,id,links,contentUrl)","@odata.count":0,"value":[
] }
What needs to be done for my client to get not just the section in the shared notebook but (more importantly!) the notes in that section?