In the 1950s the United States government made contact with a race of technologically advanced beings known as the Ghin. The Ghin leader, a brilliant scientist named Cronos, had come to earth seeking a cure for a deadly plague threatening to annihilate his race. Cronos believed the cure to the plague could be found within human DNA, which was remarkably similar to that of the Ghin.
Embroiled in a deadly cold war with the USSR, the United States government agreed to provide Cronos asylum and, more importantly, access to US citizens as test subjects in exchange for Ghin technology. With the bargain struck, a group of high-powered individuals known as the Majestic 12 initiated a secret government program. The project, codenamed Aquarius, saw the creation of several underground facilities classi ed far beyond top secret. For over fty years, Cronos conducted his gruesome experiments on an unsuspecting population with the aid of those who were entrusted to protect them.
With the fall of the Soviet Union and the end of the cold war, relations between the Ghin and the US began to deteriorate. Only Cronos’ threat of exposing the Faustian deal kept the US government continually supplying test subjects.
Less than twenty-four hours ago, several test subjects managed to escape the Subterra Bravo facility. Their actions led to a complete breakdown in relations between the human corroborators and Cronos’ minions. Having planned for this eventuality, the US government has enacted Omega Protocol . . .
I looked up the word corroborate but I can't grasp the relation between its meaning "to confirm/support a theory/finding" and these "human corroborators" from the text. What are they supposed to confirm?