Is it possible to add unmatched songs to an album, locally?

I have the last song of the album broken up into two songs, so the last one becomes unmatched. Is there a way I can tell Picard to just save it anyway?

You should choose the correct - really matching - release with 10 tracks:

The one, where the 10th song is called “Songs” (not the Vinyl-LP with only 9 tracks).

Right click on the release name and click on “Other versions”: