Remove blendshape data from imported blender animation

I made a model in blender, with blendshapes and animations.
The animations do not make use of the blendshapes whatsoever, but when I inspect them in unity, they all start with a keyframe that sets them to zero. The animations are read-only. Because the animator has grabbed the blendshapes, I cannot edit them in runtime through script.

How can I stop the animation from touching the blendshapes, OR import the model from blender in which its animations do not interact with its blendshapes?

I would like to avoid making a duplicate of my animations, for filesize reasons.

 

Same here, looking for solution

 

Same problem. Any updates?