TVNZ spokeswoman Georgie Hills would not reveal the nature of Fair Go's investigation into the accused but said Harcourt would present a story related to the inquiry.
Asked if footage from the alleged assault would be shown she said: "All I will say is tune in on Wednesday night".
Fair Go's Facebook page was inundated with messages of support for the reporter.
Harcourt posted a brief message saying his shoot at Mt Maunganui was "more eventful than planned" but he could not comment further as the matter was before the courts.
"I'm fine apart from a bit of a sore head, though the makeup team might have quite a challenge on their hands getting me presentable for this week's show," he said. "Well, more of a challenge than usual."
In his earlier investigation, Harcourt exposed the car yard for offering $800 for a repossessed car it later put back on the lot for $6995.
The Fair Go probe also revealed the arrested man runs a finance company used by the car yard which charges rates of 30 to 35 per cent and is aimed at beneficiaries and low-income earners.
- additional reporting NZPA
