He said Heaven-Leigh was also "strongly opposed" to Nikau being discharged without conviction.
As he passed sentence on Nikau - convicting him and ordering him to pay reparation of $200 within 21 days plus court costs of $132.89 - a gasp was heard in the public gallery of the courtroom.
Nikau left the court with his wife and declined to comment outside when asked about his reaction to the decision.
But Mr Gotlieb later told the Herald that Nikau was "gobsmacked" by the court's ruling and had lodged an appeal against both the sentencing and conviction before leaving the court.
He said he wanted to call to the defended hearing an independent witness, who watched events between Nikau and his daughter unfold, but his request was rejected.
Mr Gotlieb had earlier told the court how Nikau was "a huge, strong man" but merely pushed his daughter away, placing his thumb on her throat not wanting to harm her when the two confronted each other outside the Huntly police station.
He said a criminal conviction would have a serious effect on Nikau's family, his various business interests and the charitable organisations he works with.
He also provided several statements which testified to his client's good character.
"I'm struggling to think of someone more deserving of credit for what he's done," said Mr Gotlieb.
Nikau, who entered a not guilty plea to the assault charge when he appeared in court in March, earlier told police how he no longer had a relationship with his daughter.
He claimed Heaven-Leigh was a liar, a cheat and a thief with no fixed abode.