13 of the squad's players signed a complaint letter against the Austrian, stating that they no longer wanted to play for him following allegations of such behaviour.
Heraf, who also doubles as New Zealand Football's technical director, was accused of creating a culture of fear in the dressing room following taking up the role last year.
Heraf's methods on the pitch had also come under criticism from the Ferns players, who was accused of being overly defensive in a game against Japan. He defended his tactics by saying that there was a "big difference in quality between the two teams".
In response to this particular matter, the president of New Zealand Football, Deryck Shaw, said:
“We hold player welfare as a matter of utmost importance and that is why we are conducting a thorough, independent review,
“There is no place for inappropriate behaviour of any kind with NZF. We are focused on creating an environment which gives the Football Ferns, and all of our national teams, the best chance of winning on the world stage.”
The allegations come just a month on from the nation's football association announcing that the men's and women's teams would be given equal pay.