I'm not sure that's exactly what happened, but your point could still be valid. It did appear that the line judge signalled 'unsighted', but the umpire still treated the situation as a challenge by the Koreans. This would make sense if the umpire had made the line call himself, which I believe he can, just as he can still overrule calls by line judges; however, I did not hear the word 'correction'. Nor did the umpire say the words Kim So Yeong is challenging the call. The shot was called "out". However, the umpire did say both Challenge unsuccessful and One challenge remaining. If this were an invocation of HawkEye due to an unsighted line judge, neither of these things should have happened.
As I say, though, even if the umpire in fact made two mistakes - 1) subtracting a point that had already been earned and 2) penalizing one team for losing a challenge that the court officials should have been taking responsibility for themselves - then your point would still be valid because the root situation of having the confluence of an available IRS system and an unsighted line judge is the 'new situation' that your are referring to, at least if I understand you correctly.