Not sure what is going on with this Soundtrack currently. I did a keyword search and only one track out of the bunch is currently available to me, and I have a U.S. Spotify account currently.
Spotify wants all the world's music, and they're working hard on making this happen for you. However sometimes agreements can’t be reached with the artist or label or a change may happen in music ownership.
Spotify adds thousands of albums and artists are added every day. If you can’t find an artist you’re looking for, they may appear (or reappear) soon. In the meantime, feel free to contact the artist or their label to ask when they plan to be on Spotify.
It's what happens when they remove streaming rights for those albums/tracks. Maybe the label no longer have the rights to release it in your market.....maybe someone just pushed a button by accident :)