Hello. Avatars, so that they will properly import and work in FaceRig, must be created following our guidelines and documentation: https://drive.google.com/file/d/0B9A2HzJCWwFWYnN6SFRPbW1mRWM/view?usp=sharing

If you're missing both the idle animation (which is the pose from which the avatar is starting its animations) and the geometry file (which contains the avatar's bones, hierarchies etc), then that avatar wasn't made specifically for FaceRig.