He first appeared on Saturday when he was remanded in custody without plea.
His name, occupation and address were suppressed so he could tell his family about the charges and his lawyer Adam Couchman said that had not been done over the weekend.
Judge Nicola Mathers extended the suppression order until Thursday at 5pm to allow the phone call to be made.
Witnesses who spoke to NZME. News Service shortly after the incident spoke of hearing screaming and seeing people covered in blood.
One said Ms Rani had just sat a level 7 IT exam when the alleged offender met her at the school.
The young woman had arrived in New Zealand from India only last year. It is believed her father died when she was a child and her mother passed away this year.
Another friend said her India-based brother was her only surviving relative.
The witness had been studying IT with Ms Rani for the past 18 months and described her as his best friend.
"She was very kind, she was a very friendly girl. She always took some food for me."
He said a man arrived at the school about 8.30am and had waited for the woman to finish her exam.
Several people had seen a knife and she was warned not to go downstairs.
The man will appear in the High Court at Auckland next month.