NZ provide a page that matches LH booking classes to levels of Airpoints and status points.
The link is
https://www.airnewzealand.co.nz/star-alliance-lufthansa
My interpretation is that LH C class ticketed flown on NZ metal earns Airpoints/Status points as full Business class.
That table is relevant only for
earn on LH metal.
Your situation is LH ticketed but flown NZ metal. Hence I think it is still likely that you’ll earn per the app, and as I noted that amount on the NZ calculator suggests earning as if NZ J class. Of course, great if there's a glitch in your favour!
Please report back the outcome.