V557 was a Voc that worked for The Source.
V557 was driving a Flyer that stopped next to Liv Chenka and asked her to get in. After becoming suspicious Liv was persuaded by The Source and V577 drove on.
A day later V577's Flyer saved Liv and Tula Chenka, from being shot. It instructed them both to remain seated but when they discovered The Source was a Robot avatar both it and V557 shut themselves down. (AUDIO: Machines Like Us)