Saving Clips with Encased Keys (New for v7.21) not work for Non-Human avatars.
The motion clip and its encased keys is flattened before they are saved as a motion file (*.iMotionPlus) for Non-Human avatars. Therefore, when i apply the saved motion clip file back on to a character, the encased keys is missing (because they are completely merged into the clip before the clip is exported).
Did you save iMotionPlus? "Saving Clips with Encased Keys" function is only for iMotion，and it must save from timeline "Save Clip". If you save iMotion from Content Manager，there will no encased keys in motion clip.