If your friend is applying for a NZ visa on the grounds of qualifications and skilled employment, he MUST follow what INZ says is necessary. In the first place, unless his qualifications are on the List of Qualifications Exempt From Assessment for his country (including the name of the qualification under the awarding institution, and mentioned for the year in which he graduated), see here,
https://www.immigration.govt.nz/opsmanual/#35171.htm, he will have to have them assessed by NZQA. Then, if he needs the points for the job being on a Skills Shortage list, many kinds of engineering job include the requirement either to be registered with Engineering New Zealand, or to have had an assessment from them so they issue a letter stating that his study meets the requirements towards Chartered Professional status.
Summing up, if his qualifications is not exempt, he needs the IQA from NZQA. If he needs bonus points for being on a Skills Shortage list, and if his job says so - check here
http://skillshortages.immigration.govt.nz/ - he may need to be checked out by Engineering NZ. (The two verifications are not alternatives, and don't cancel each other out as far as INZ is concerned - they're for different purposes.)