The intelligence gathered by the Mirror Raiders eventually made their way to Task Force Predator through some obscure means.
Even if the Mirror Raiders were no longer allowed to leave Ulimo Citadel, they still possessed several sophisticated ways to transmit data.
Before, Abis and Rodan were very reluctant about using any of those means. Once exposed, they would fail their mission and doom the lives of every Mirror Raider!
They only took the risk after capturing and interrogating several important pirates, most notably the technicians and officers of the Dry Snakes and Xona Stalkers.
It was very difficult to capture them without leaving behind a trail. In order to frustrate any investigations, some of the Mirror Raiders deliberately stirred up trouble.