I'm establishing a resources hub in moodle where I would like specific teachers across our organisation to only contribute to specific sections/topics. Is there a clean way I can restrict Teacher-A to only access Section A, and Teacher-B to only access section B... and so on.
You can restrict access to whole sections, yes - but I think you’re actually asking if TeacherA can only edit sectionA but view all sections. And TeacherB can only edit sectionB but view all sections. Is that right?
If not, and you do actually want TeacherA to be restricted to only sectionA, then one of the options is to restrict access based on information in a user profile field: see https://docs.moodle.org/37/en/Restrict_access_settings#User_profile. So you can restrict access based on a teacher’s name.
But if you want what I think you’re asking, then that’s going to a lot more difficult as permissions are based on role and not individuals. If it was individual activities, it might be slightly easier as you can assign local roles, but that doesn’t work for whole sections (although it has been raised before - see MDL-38762).
I'm open to any other kind of trickery I can employ to achieve a similar result. H5P iframe embedder in Section-A to a separate course for Teacher-A