...in which case the legislation you refer to still doesn't apply. RD makes a valid point.
More to the point - and I don't know the answer to this - it really comes down to who the pilots work for. As Mt Cook is a wholly-owned subsidiary - in other words, a separate company which has the majority of its stock owned by a holding company (Air NZ in this case) - it could be argued that the pilots work for Mt Cook, not Air NZ. In addition, Mt Cook could be shut down by Air NZ if they decided it was uneconomic. If another wholly-owned subsidiary then offered the redundant crews jobs (ie Freedom Air/Zeal320), you would have a tough time applying subpart 6A as the relationship between the companies is not the same as that described by subpart 6A.
Anyway... none of that is the point, is it?