"I'm not making any comment about the future at all. I have no idea what the world will look like in six months time."
However Powell said the chairman needed to be held to account over his role in the expenses scandal. Murray resigned in October during an investigation into his spending of $218,000 in three years.
"This fiasco is a public embarrassment to Waikato DHB and is an insult to the dedication of the overworked health professionals that keep patients safe despite this leadership scandal. It is made worse by the board chair resembling a possum in the headlights," Powell said.
Powell said the release of Murray's expenses last week, which showed he spent $91,506 in the last financial year, raised some serious questions.
Among the expenses were receipts which showed he spent double the $25,000 agreed to relocate him from Canada, travelled to New York, Los Angeles, San Francisco, Vancouver, Moncton, Montreal and Sydney over three years and hired a rental car in Canada for a month at a cost of $1193.
"Why did Mr Simcock allow Nigel Murray to live in taxpayer-funded accommodation for six months when normally this would be for one month?," Powell asked.
"Why did Mr Simcock wait until July this year to investigate the expenses issue after being raised by courageous senior managers when the State Services Commissioner had raised concerns a year earlier over the failure of Nigel Murray to provide the standard expenses report required of all DHB chief executives?"
However Simcock refuted Powell's claims and said all but one of the expenses in question were unauthorised.
Details about the activity given for the expense in question that was authorised were now being disputed, but legal restrictions meant Simcock could not give further information about it.
In response to his authorising of accommodation costs, Simcock said he wrote a note telling staff not to pay more than $25,000 but it had somehow been bypassed.
Simcock also slammed claims that the DHB did not carry out its due diligence and said recruiter Sheffield Search carried out thorough reference checks on the DHB's behalf and even went back to the references including Fraser Health in Canada and Southland DHB after the ASMS raised its concerns.
He said all the references dismissed the concerns around Murray's actions in previous roles.
Simcock says of Powell: "I just reject simply his claims that both the process was superficial and what he is saying about both of those situations."
Simcock said he had never met Powell or spoken to him.
Waikato DHB had released all the information it believed it legally could at this stage, but was awaiting the outcome of the investigation by the State Services Commission launched by new Health Minister David Clark, Simcock said.
"I think that will allow things to become clearer and in more detail if they choose to. But it is certainly a chance for the Government and the minister in particular to gain confidence in the processes we've been through. I've got no doubt that the processes we've been through are absolutely thorough."
However Macpherson said Simcock needed to resign so the new interim CEO could lead the organisation "with a board with as little baggage arising from past problems as possible".
"He is doing our organisation no good by staying in the position, and causing the focus to be on himself and his position.
"As Chair, Bob has tried to do his best for the DHB since he was appointed. However, the fact remains that some serious problems have occurred on his watch, and as the chair appointed by the previous government, he is accountable for them, and needs to accept that accountability."
