You appear to misunderstand how licensing music for Rock Band Network works. (This isn't an insult, just an observation...I see it a lot.) Rock Band Network authors can't add any songs they want in the game; we need to secure the rights to the songs in order to work on them. If we could do whatever we wanted without needing permissions, I'd have already put in all of my favorite bands.
In order to get Chiodos songs, their label must be willing to license them to an authoring group, and usually the band or label pick the songs that go on the Network.
Also, as Coltfan1223 said, "Caves" is currently in the system, which is a song off of Illuminaudio, I believe. It'll be available whenever it passes through the Peer Review process.
You can learn more about how RBN operates at http://creators.rockband.com.