So I finished doing this test and thought about posting it here.. Then I saved the project and Adobe Animate did this!!
expressiontest.mp4
I found it hilarious and ended up "Fixing the animation".. which translates into animating frame by frame and thats why it looks giggly at the start
expressiontest_1.mp4
But as far as I know.. there's no real solution to the bug.. I tried everything!!