Kara and Barry weren't the only ones Music Meister wanted to "help". After his time in the Speed Force, Wally needed an extra push to get Kid Flash back in the game. He found it when it came to stopping the baddie.
One mystery I cannot figure out is why some people come into our lives and why some people go. Others become a part of you. Some friendships feel like they'll last forever and others end far too soon. Not every friendship is meant to last forever. What does last forever is the pain when that person is gone.