Hey there, interesting question - it's possible 3 tracks did not make into the soundtrack, but I'm not convinced we missed any more than that.
The one you speak of sounds a lot like #1 below to me. After looking, I can only find 3 others that I don't think are included (#2, #3 & #4 below) with the current soundtrack. My apologies, let me know if any of the ones below are/are not from the game and I'm sure I can make them available:
1. Piece by Piece - a 5 minute track that comes included with The Cat Lady soundtrack (5m35s)
2. A vocal track that mentions "whispers" in the opening line (3m40)
3. A guitar riff (or two) (0m17s)
4. Starts with a "bell" sound and has lots of thumps and a synth in it (1m25s)
just saw the post sorry, I thought nobody was going to answer me so I never checked again :P, you are right about the tracks :)
if you listen to the music.vox file in the game you can hear them too, and in the cat lady soundtrack it's the 39th track called peace by peace like you said (amazing song really like edge on the cat lady )