You’ll be fine. If you have a public transport ticket, or a rental car and stop to refuel, I’d keep receipts. Turn on google maps locations.

If any questions on arrival I’d say no you haven’t been in NSW. Technically due to geography of airport / roads you may have but for Covid travel purposes, no you haven’t. Don’t refuel in the NSW part of your drive!

Not sure how NZ is functioning and whether they have access to police info in Oz but basically thanks to “pandemic laws” police can track your cell phone and tell if you’ve been somewhere you shouldn’t have. Hence… there’s no way I’d lie on border passes. People have been sprung retrospectively!