The Australian-owned trade school company facing a fraud investigation is also the subject of yet another government investigation.
The Overseas Investment Office (OIO) told RNZ it would investigate the education group, Intueri, after it was allowed to purchase the New Zealand Institute of Sport.
Questions have arisen over how the company could have met the good character test required of foreign buyers.
Australian-owned education group Intueri has been under scrutiny since it received funding for non-existent students at its dive school between 2009 and 2014.
Last week, Intueri was ordered to pay back $1.47 million to the Tertiary Education Commission (TEC) for enrolling the non-existent students.
Its dive school also pleaded guilty to a WorkSafe charge following the 2014 death of a student.
The Serious Fraud Office is already looking into discrepancies at the company's subsidiary, Quantum Education, which offers certificates in diplomas in subjects including tourism, counselling and computing.
Late last year, the office gave Intueri permission to buy the New Zealand Institute of Sport, which offers diplomas and degrees in sport and fitness.
OIO group manager Annelies McClure said it was aware of the company's problems, but was satisfied the company still met the good character test.
She said the SFO investigation was announced in January after OIO permission was granted.
"The OIO began its own investigation in February 2016 and that investigation is ongoing," Ms McClure said in a statement.
Labour MP David Cunliffe said it "beggared belief" that the purchase would have passed the test.
Intueri, however, maintains it does meet the good character test.
Chief executive, Rob Facer, said Intueri was not responsible for the problems at the dive school, which occurred under the previous owners.
He said, when Intueri did take over, it asked Ernst & Young to do a review.
That review, which identified the fake students, was handed over to the Tertiary Education Commission.
The OIO process was completed long before any issues were raised with Quantum Education, Mr Facer said.
He said the SFO investigation into Quantum appeared to date to before Intueri purchased that institute as well.