Adding some more info to this thread as it’s the top Google search for this issue. I made a small tutorial and example of connecting Dataprep and Geometry Script via Editor Utilities as Flavien recommended. You can daisy-chain them together and essentially still have a one-click ability to re-run the Dataprep recipe and then run the Geometry edits.
My method was with tags. You can tag actors via Dataprep and then find those tagged actors via editor utilities and modify their assets.