Yes somewhere in HK-51's conversation chain he says none of the other HK-51 units will never be active and states it is an "unfitting end". He later states he will be a Vanguard for the 51 series. The codex says the the design plan were abroad a derelict vessel which has since entered a black hole
Why hasn't anyone explored another galaxy? why didn't the sith just settle on a new galaxy after the hyperspace war? Is hyperspace only usable in this galaxy?