Hello guys! I just made a tutorial on how to create an open mouth blendshape that also includes the teeth so they open too, this will be a good start till they fix the issue.
You just need the following applications:
Blender
Mesh Baker pro for Unity
MorphMixer for Unity

Great work on figuring out this workflow on your own.
We figured out a similar path through Blender and is indeed a great way to fix this.
The other method is using a C# script and controlling the CC_Base_Teeth02  from => Postion Y  0.0086 to 0.0190  =  0.0 to 1.0 (100.0%) to set ratio and  with the Mouth_Open blend 0.0 to 100.0% driving the Position Y. Works really well.
If curious send a PM and I can give you a cleaned up C# script.

Again...great work on figuring this out....which should not be an issue in the first place.

Cheers
O

Thanks!! And i unfortunately i can't use any scripts.  The program i use the characters for doesn't allow external scripts.  I import my character into another game where i can then act out my animations and record my voice that produces the blendshapes.  Its for the HTC vive or oculus rift.  Vr is fun 😁