Mixamo IK Ring blender export for Unity Issue

Hi there!
I am using a Mixamo character in blender. I used the Mixamo control Rig plugin. I then mixxed mixamo animations with custom animations. This is  to be used in Unity  With the Humanoid set up. 
The character in Unity is a CC3 generated character. 

My issue is that even though the animation in blender works and looks as intended, during the export, the fbx skeleton is wrong and the animation(s) is distorted both in unity and in an empy blender project. Basicaly the problem is on the fingers and legs.
Any help will be appreciated.