The License Admin page is the user interface to the license_ref table, which keeps track of canonical license text and other information about the license. When you are using the License Browser and click on a file, the web interface will show you the file text, its path in the upload and what the license is. For example, it might say:

The Nomos license scanner found: GPL-3.0+ [Edit]

In this line there are two links. One on the license name (GPL-3.0+) the other on [Edit]. If you click on the license name, the canonical license text (from the license_ref table) will be displayed in a new window. That's all the license_ref table is currently used for.

The license scanner (Nomos) does not use the license_ref table. Nomos is a fingerprint scanner. It basically looks for expressions (sometime in proximity to other expressions). The only way to add new licenses to Nomos is by changing source code.