Nothing to do with queries.
BO A and B. A has a reference attribute allowing multiple B's. B has a field X where I setup choices in the GUI tool AND allow admins to add choices on the fly using the user defined choices feature.
When viewing an A, there is a table of the related B's in the form, which is editable. The field X with the choices shows a dropdown of the allowable choices. This dropdown ONLY shows the choices provided in the GUI tool, not the ones added later by the admin.
Hopefully I am doing something wrong, but otherwise, in this case, the user defined choice list is broken and useless.