Permissions to edit Catalog Custom Fields

I’ve recently created a new Asset Catalog and need to grant permissions to the users who will administer that catalog. I cannot figure out how to grant them permission to modify Custom Fields via the Catalog’s link to Asset Custom Fields:

https://help.reed.edu/Admin/Assets/Catalogs/Modify.html?id=6
Admin > Assets > Catalog > select catalog > Asset Custom Fields
The page just says “(no custom fields)”.

However, if they visit a slightly different page they can edit way more than I’d like:
https://help.reed.edu/Admin/CustomFields/?Type=RT::Catalog-RT::Asset
Admin > Assets > Custom Fields

Ideally they should be able to create, view, and modify fields that have been Applied To their one specific Catalog, but not all fields in all catalogs.