The link had already listed those VS, HX, and KA lounges are contract lounges, which means if you are not flying on that particular airline, you can't use those lounges, e.g. BR use VS clubhouse as a contract lounge in HKG, OZ use CNAC lounge as a contract lounge in HKG, LX use the travelers lounge as a contract lounge in HKG (previously was even using CX lounge !)

Also, to access contract lounges usually require a lounge invite in order to access, which if you qualify for one of those you would be issued a lounge invite at check in, you can't show up in one of those lounges by just showing a *G card and *A same day boarding pass, they will deny you right away.