Someone in your wife's situation has to show that she COULD go back to a life in her own country if she couldn't prove her case for a partner-sponsored visa in due course, and that she understands that she would have to leave NZ at the end of the visitor visa if she didn't get a different kind granted. But her case is not the same as someone who ONLY want to make a short trip to NZ and then go back to their home, life, and job, elsewhere. Bona fide (good faith) involves telling the truth to INZ, letting them know what the applicant honestly intends. As the new wife of a NZ work-visa-holder, it is obvious that she is not ONLY a visitor. There will need to be a cover-letter explaining.