I tried it David.
Not sure what way you used in the Mesh displacer.
*If you animate the object with a powerfractal with the Scale tab it worked.
*If you put a transform input node (not sure about "world space") between the powerfractal node and the object and change the position in time it works.
*But i could not animate with the "Animation" tab in the Powerfractal node.
I will have a closer look on the last part.Maybe it was too slow?
Just to see the animation easier i used a basic high poly ball object.
It might be harder to see in a tree object maybe with small displacements?
Edit: No i could not animate with the Animation tab (4D noise).
Other then this, Mesh displacing should work mostly.The shadows are correct too.