I have posted this related issue in stackoverflow, as the group name tag is a useful reference to access for ifc (Building Standard) conversions to obj. Since the group gets a persistent GUID that can be re-referenced.
An alternative or a parallel feature to aid ifc usability of vtk's features is to handle the "name" tag in a glb file eg; "name":"3rPX_Juz59peXXY6wDJl18", but I am unsure if this handle is already possible. If it is already implemented, I would appreciate some direction on how to access it.