Something Ginny said to her when she was explaining how she first got mixed up with Rodolphus years earlier stuck out in her mind. Ginny claimed that thanks to the wards Rodolphus set up on the house he let her hide in during her pregnancy that not even Draco could track her with his spell. The wards had been removed, but what about other places that were similarly protected? She would never forget how Draco promised her that William Wood wouldn't be able to track her to his flat. Was it possible that Antonin was just being held somewhere that the spell wouldn't work?