Sounds like the extortion scammer is got a new number.In all reality he is the fake "girl", there never was a real one. The thing to do is file a extortion complaint with the local Law enforcement and IC3, the cyber crimes division of the FBI. If he is texting, you can also include those attached to the complaint as they are evidence against him.
www.naag.org (you can find your state AG at this link).
http://www.ic3.gov/default.aspx
http://www.fraud.org/
http://www.stopfraud.gov/report.html
Tip off FBI about this extortion attempt by filing form at: stips.fbi.gov/