In general, having a work visa doesn’t give you any extra or super rights in employment situations. Migrants must be treated the same as New Zealanders. So, the short answer is yes – the accredited employer can make his client redundant just the same as if he was a NZ citizen.
The issue for the migrant becomes the validity of his visa. As it stands, once his employment ends his visa (and that of his family) becomes invalid. Technically he needs to apply for a visitor visa to remain in New Zealand and find another job. Both are way easier to say than do. We have had nothing from the Government for the 1000’s of others in a similar situation as to whether there will be any grace or easing of conditions. Its an uncertain time and we are telling people not to panic as they will not be deported or held accountable if they can’t leave voluntarily.
Your client should get some advice about what to do next. You yourself should not give any kind of immigration advice, even for free during your sessions. That’s a breach of the Immigration Advisors Act and you could be sanctioned for it. If your client wants some free advice, point him at the Citizens Advice Bureau who have the national contract to such advice.
Hope that helps.