Hello @Boony2000,
thank you for reaching out to us. There is unfortunately no guarantee that everything that should have an id symbol has an id symbol. Or more directly, there are other cases where one most use integer instead of symbols. This mostly happens for message symbols, but there are also a few cases for NodeData types, e.g., there is no Omgcloner. These mostly did happen as an oversight of the person who did implement these functionalities, there is no higher meaning behind it.
As a developer one must define such symbol locally or hardcode it. We are currently not planning to update the symbols in this regard.
Thank you for your understanding,
Ferdinand