I believe Jesper Kyd (who was the composer for Assassins Creed II and past Hitman games) should've composed the soundtrack for this game. Any person who has heard the soundtracks from other Hitman games and/or Assassins Creed II knows what I'm talking about.
"It's by doing whatever that one becomes whoever" - Remi Gaillard PSN: Black_Hound12
He wasn't available to do Absolution's soundtrack since at that time, he was making the soundtrack of Assassin Creed III (in fact, he did all console AC games).
No... Jesper Kyd did not compose the soundtrack for AC3... Even if he did, that would not have stopped him from working on Absolution at the same time. Composing music for video games / film isn't really a "one contract at a time" deal like film acting. Regardless, having him work on Absolution would have been sick.