The only mention of NSA seems to come from Kim... His logic appears to be that as a Five Eyes member the NSA and GCSB have some shared resources and that means the NSA used those resources to spy on him. That might be true, but he has no evidence that the NSA cares one bit about him. I seriously doubt the NSA was tasked with working a non-terrorism related piracy case, but that's me. http://www.nzherald.co.nz/index.c…
So in this case, the NSA would have a perfectly good reason to have him under surveillance. Primarily, when you think about how Hollywood and the music industry was impacted economically (and culturally) by his company. The DOJ were justified in requesting technical help, and would expect get intel from the NSA (Who in turn would request assistance from the NZ Folks) to support their case.