For the Fantasia problem, try a consistent title. In absence of opus numbers, title consistency becomes more critical. Add “, for guitar & orchestra” to the top one.
As for the Concerto, I still feel your pain. I have five Boleros in my system. But they are split into two groups and the groups don’t talk to each other. Still scratching over that one.
One other thing: I see no TIDAL on your screen? Are you subscribed? Having TIDAL in the mix makes composition IDing a better possibility. Add a TIDAL Rodrigo to your library, and it could clear up.
I know, I know. You shouldn’t have to do that. John
Check this post: Grouping tracks into works