Here's the Brawl music credits. Note how a select batch of artists [including Shogo Sakai] are not listed under "Music Arrangement" despite their obvious arrangement credit. They are the inner staff, and therefore the most likely to have made all the variations of the main theme.
http://www.mobygames.com/game/wii/su...-brawl/credits
http://www.smashbros.com/en_us/music/music24_list.html
Main Theme Music: Nobuo Uematsu, Taro Yamashita, Taizo Takemoto, Oriko Takahashi, Ken Nishikiori (PONY CANYON INC.), Hirofumi Sako, Mio Noguchi, Kimio Yamane, Otohiko Fujita, Kiyoshi Sato, Yuki Hasegawa, Satoshi Shoji, Masashi Maeda, Eric Miyashiro, Tomoyuki Asakawa, Masatsugu Shinozaki Group, Katsuhiro Kobayashi Group
Music & Sound: Takahiro Nishi, Shogo Sakai, Masaaki Iwasaki, Yutaka Iraha, Keigo Ozaki, Kentaro Ishizaka
Music Arrangement: Akihiro Honda, Asuka Ohta, Hirokazu Tanaka, Jun Senoue, Kenichi Okuma, Kenji Yamamoto, Koji Kondo, Masato Kouda, Minako Hamano, Noriyuki Iwadare, Seiji Momoi, Tomoko Sasaki, Toshiyuki Sudo, Yasufumi Fukuda, Yoko Shimomura, Yusuke Takahama, Arata Iiyoshi, Hajime Wakai, Jun Fukuda, Kazumi Totaka, Kenji Ito, Koji Hayama, Masafumi Takada, Michiko Naruke, Motoi Sakuraba, Ryoji Yoshitomi, Shota Kageyama, Toru Minegishi, Tsukasa Masuko, Yasunori Mitsuda, Yuka Tsujiyoko, Yuzo Koshiro
*Takahiro Nishi: Battle! Dialga / Palkia, Mona Pizza, Environmental Noises, Theme of Tara
***Shogo Sakai: Main Theme (New Super Mario Bros.), Luigi's Mansion Theme, Underwater Theme (Super Mario Bros.), King K.Rool / Ship Deck 2, Title (The Legend of Zelda), Wildlands, The Legendary Air Ride Machine, Road to Viridian City (From Pallet Town / Pewter City), Battle! Wild Pokemon (Ruby/Sapphire), Route 209, Fire Emblem Theme, Underworld, Mario Bros., Porky's Theme, Mother 3 Love Theme, Snowman, PictoChat, Mii Channel, Great Temple / Temple, Super Smash Bros. Brawl Main Theme
***Masaaki Iwasaki: Overworld Theme 2 (Super Mario Bros.), Chill (Dr. Mario)
**Yutaka Iraha: Hyrule Field Theme
*Keigo Ozaki: Clu Clu Land, Shadow Dragon Medley, WarioWare, Inc., Go K.K. Rider!
***Kentaro Ishizaka: Opening (Super Smash Bros. Melee), Underground Theme (Super Mario Bros.), Waluigi Pinball, Title (3D Hot Rally), Jungle Level, Boss Theme Medley, Corneria, Star Wolf, Pokemon Center, Winning Road - Roy's Hope, Stage Clear / Title (Pikmin), Unfounded Revenge / Smashing Song of Praise, You Call This a Utopia?!, Town Hall and Tom Nook's Store
*Came from Square
**Came from Hudson
***Came from HAL Laboratory, Inc
Two other things to note:
-The presence of Yoshinori Kawamoto in the original supervisors credits [and not Yoshie Arakawa] tells me that he was the one responsible for composing and arranging the themes from Star Fox: Assault in that game (Space Battleground, Star Wolf's Theme, and Break Through the Ice Field), as Star Fox: Assault was the only Namco-made game represented here in terms of music.
-Naofumi Hataya's presence in those same credits tells me that he was the one who composed Angel Island Zone, as none of the other Sega-made tracks (including the lost one) were definitely composed by him. As for why Hataya is not listed in the Sonic 3&K credits, the answer is simple: he is either half of, or the entirety of Masayuki Nagao, a most suspicious character at Sega [none of the music composers or the Sega Sound Team from S3&K are here either; neither is Masafumi Ogata]. Also keep in mind that the majority of the Sonic sound effects came from Sonic 1, which neither "Hataya" nor "Nagao" nor "Ogata" worked on. Looks like Sonic Retro was right.