Deform a group with deformers inside

Hi to all,

I am creating a character who is a Phone. The phone has a face on the screen. The face has the usual deformers on the eyes, brows etc.
The face is on the screen, which is the body. Now I want to be able to deform the body (and the screen/face along with it) with a simple two point curve deformer.

But I can’t manage to make it work. I find solutions for kinematic output, so it pins it to one deformer point. But what I need is just a global deformer which influences everything inside my group

How can I achieve this?
Thank you.