So, this is a bug from live so I don't know if it's fixable but during this mission you have to rescue the freedom phalanx from a series of EB's and they are supposed to follow and help, then you use those freedom phalanx members to help you beat the Jade Spider
The bug is that they get stuck inside the world geometry, and even if you can get them to the jade spider the jade spider's hitbox is in the air and the freedom phalanx will simply not attack it.