So, I tried this but unfortunately, it doesn't work (or more specifically, I couldn't get it to work).

The eyebrows are props... all of the fiber are props, even the hair I built in Poser Pro.

The Figure menu only allowed me to Copy Morphs from the fitted jacket; there was nothing else in the dropdown to copy morphs from under the Figures > Copy Morphs menu.

So I selected Copy Morphs from the Objects menu, and I copied the morphs from James Brows All, Brow Up, Brow Down, etc. to the fiber eyebrows.

No change in the eyebrow fiber movement; they stay static while the brows move behind them.