In RETURN OF THE CONDOR HEROES '83 (I'm suspecting TVB's hand again, so I'm referring to the series), when Gung Sheun Tze first confronts the wife (Kau Cheen Chek) whom he thought he had eliminated long ago, he deliberately mentions the fates of her older brothers Kau Cheen Yan and Kau Cheen Cheung to expose her true identity. Gung Sheun Tze reveals to his ex-wife that years ago (during LOCH), Gwok Jing and Wong Yung caused the death of Kau Cheen Cheung and were also instrumental in causing Kau Cheen Yan to become a Buddhist monk under South Emperor 1 Deng.
The question is: did Gung Sheun Tze actually know all this (in the novel) and if so, how? Passionless Valley was extremely isolated from the outside world. Not only was the valley geographically far-removed, but its inhabitants practiced isolation. Passionless Valley inhabitants did not travel outside of the valley, nor did they receive many guests from the outside. Gung Sheun Tze was unlikely to have known much about the going ons in the wulin outside of Passionless Valley...even events as momentous as Kau Cheen Yan's becoming a monk. Indeed, it's strange that Gung Sheun Tze would even know of the Greats, let alone Gwok Jing and Wong Yung, in his isolated position.