So she decided to use a recovery service to milk you. If NC isn't trying to recoup money they are dishing out to her, then this is simply her doing. She could drop this all together and you could make an agreement outside of court with the assistance of an atty.
Has custody been established in any type of court order? IIRC, you weren't ever married, so I'd bet she has full physical/legal custody.
A lawyer does wonders in situations like these.
