All 5 composers are credited with the games music, as stated at the end of Skyward Sword in the games credits. If we want to split hairs, the tag should actually read "Hyrule Symphony Orchestra - Ballad of the Goddess (From Skyward Sword)" as they are the performers of the soundtrack, and typically you put the performer of the song instead of the composer of the track in question, but that's just far more complicated than need be, lol.
Koji Kondo only composed a single song for Skyward Sword, which is the one playing in the opening movie.
My guess is this was composed by Hajime Wakai though I can't say for certain.
If only the darn disc came with some credits.