Ms Richards said Hosking had indicated he had not declared the deal because he was at TVNZ for only about four hours a fortnight.
"He said nobody had asked him about it, but we pointed out that declaring issues was one of the terms of his contract," she said.
He had told TVNZ he sometimes worked as a master of ceremonies for the casino company. Ms Richards said TVNZ did not know the terms of the arrangements, the form of payment or the amounts involved.
However, it is understood that his remuneration from SkyCity amounts to thousands of dollars.
"We have asked him to come back to us and give updates on his roles outside TVNZ, and Mike was perfectly fine with this," Ms Richards said.
She said the Close Up restriction applied to items about the SkyCity corporate entity and not issues such as problem gambling, which Hosking would still be able to handle.
Hosking had been involved in Close Up items about gambling, and had taken an anti-gambling approach.
"It will be for the producer to decide on a case-by-case basis," Ms Richards said.
SkyCity has been in the news over children being abandoned in a car in the casino's carpark and - in the past - the use of the casino for money laundering.
The Ministry of Economic Development has been negotiating a deal in which the Government will ease limits on the number of poker machines at SkyCity in return for the casino firm building a $350 million convention centre.
Newstalk ZB has taken a different approach, and he is allowed to talk about SkyCity when he is on air.
The Radio Network's general manager of talk radio, Dallas Gurney, said Hosking was a contractor and had declared a relationship with SkyCity from the start.
"The policy is that if the topic of SkyCity came up on air, he would make a full declaration of his interest.
"We are aware of any external potential conflicts, and if they occurred, Hosking would tell listeners."
