I think Poser changed how actor groups were represented, a version or two ago, after Ockham's script was released, a change that may have been working toward the alternate skinning methods Poser now uses.  IIRC, in the past Poser did not list the actual body part groups (such as "head") among the geometry groups listed by the Grouping Tool.  That change to Poser may be affecting how the script functions.

I typically use the Morph Trimmer script from the TDMT downloads page, for such functionality, but I didn't give it very robust group removal functions.  It works better for stripping select material zones from a morph.  If the Ockham script isn't functioning, that might be an alternative.

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.