Can I travel back to NZ if I furnish my old passport w the PR Visa Label while traveling on the new passport?
That was discontinued a long time ago. There has been a case on the forum this year where somebody managed to get round it, but it's not allowed without some special dispensation from INZ - the airlines can get severely fined if they let someone onto a flight without a valid visa connected to the valid passport.
I suggest you talk to INZ about this - it may not be as hopeless a case as you're thinking. These days, most visas are issued as eVisas, that is, a letter sent by email giving the details of the visa that you hold, which you print off and have to carry with your passport. (There is an option to get a visa label by making an application and a separate payment, but that's a different matter.) This page
https://www.immigration.govt.nz/new-...a-new-passport talks about getting an eVisa as a replacement for a visa label in your old passport, and also mentions sending a certified copy of a passport with the application. I'm thinking that it MAY perhaps be quicker than the traditional thing of having to get the actual passport to an office, so you'd be without it. Worth asking, anyway.