The music library is not available for the public. I don't want to be toxic, but your problem has a lot of solutions. I will not give you specific recommendations, try to come to it by yourself ;)
PS. btw i was in the same spot a year ago when i wanted to add end credits music to my library on the phone to listen to it when i am in a sad mood. That one and the attempt to get a night view on CrestHaven from Coach route in good resolution to place it like wallpaper on my pc. It's funny what in the end it led me to.