Stevens said the state now felt comfortable with allowing the international arrivals into the state, saying he and the state's Premier Steven Marshall have no regrets on taking precautionary measures.
"We hadn't had specific advice in relation to the status of COVID-19 in New Zealand (when the travellers arrived)," Commissioner Stevens said.
"The health advice has been assessed by direct communication through our chief public health officer with New Zealand authorities and there is a level of comfort there in terms of the extent of COVID-19 that allows us to make this decision."
On Monday, five travellers from New Zealand arrived in Adelaide after passing through other airports from New Zealand.
All of the travellers were put into hotel quarantine, Mr Marshall told reporters, but they have since been released given the new travel advisory.
"We don't apologise for taking steps to ensure the safety of the South Australian community," Commissioner Stevens said.
"These people will have been inconvenienced for a relatively short period of time, while we made a proper assessment of the risk to South Australia."
New Zealand residents began arriving into Australia on Friday, with three plane-loads of passengers touching down in Sydney from midday.