Koru Club has its limitations. Saw a kiwi couple trying to access the THAI lounge in HKG (1 was KC, both in Y), but were being told no, just *G or biz (and first) pax could use. I assume they were on the NZ flight to AKL (but that wasn't clear). I didn't linger or intervene as I knew almost nothing about Airpoints...
Not sure what the actual rules for NZ were at that time, but the couple clearly thought KC access worked at any *A lounge...