The last transmission received from the Voyager Probe, was a message, one that could not have been created by the Voyager Probe.
The final message was a creation of the Golden Record, but it was not the Golden Record we sent. For two weeks after the signal was silent. Until it reappeared, the direction was traveling back towards Earth at over twice the speed it had previously achieved, and it was accelerating.
5 months later it was traveling three times as fast and the acceleration leveled off, the calculations made were showing a likely course that met with Pluto. It was with this information that the argument over the creation of a probe that would reach Pluto before Voyager would, and to search for radio signals that might be controlling the craft.
The fight over the probe was fierce, the Brothers of Darkness do not take lightly having their secrets examined.
We eventually won that fight, but at what cost?