Hi. No, unfortunately these can't be used in closed divisions of the competitions. Variations are by their very definition not the basic movements, but variations thereof. Therefore you can only use them in the open divisions (e.g. open bronze, open silver, or open gold).
Be aware also that open bronze tends to be more restrictive than open silver or open gold. I don't know if the NDCA has any official rules for open bronze, but movements ivolving a high degree of continuity tend to be frowned upon, as continuity is usually associated with silver level. You should also avoid highly syncopated actions, drops, and any action that lifts the leg off the floor (developes, arial rondes, etc), until you advance to open silver.
Regards,
Jonathan Atkinson
www.ballroomdancers.com