Queensland's controversial Wellcamp COVID-19 quarantine facility is still being probed by the state's acting auditor-general.
The government contracted the Wagner Corporation to build the $48.8 million complex near Toowoomba, which opened earlier this year.
Wellcamp is now owned by that company, but has been leased back to the state for 12 months for an undisclosed sum.
The government says the cost of leasing and running the complex is "commercial-in-confidence", but it noted it has not disputed recent media reports the bill is in the region of $190 million in 2022.
Acting auditor-general Karen Johnson said the Wellcamp project is being investigated after the opposition requested it in April, and there is still some outstanding information needed to complete the probe.
"Various parts of information take longer to receive than others - we are actively following up those requests at the moment," Ms Johnson told a budget estimates hearing on Tuesday.
She said the probe was looking at the procurement and tender process, and why the government has deeming the deal with Wagners as "commercial-in-confidence".
"It depends on the facts and circumstances every contract that you need to consider individually. There are guidelines. There are things you would consider," Ms Johnson said.
"Commercial-in-confidence is generally very important in the negotiation stage, not so much after the contract has been settled."
Opposition MP Jarrod Bleijie welcomed the auditor-general's investigation into the Wellcamp facility.
He said there was no reason for it to be made commercial-in-confidence as the project didn't go to a tender process.
"There was no competition because it actually never went to tender, so no other businesses had the opportunity to put forward to the state government their proposals for quarantine facilities," he told reporters on Tuesday.
Mr Bleijie said he was "concerned" the auditor-general is still awaiting documents from the government, as unearthed in Tuesday's budget estimate hearings.
On the weekend, the government defended the Wellcamp project after it admitted spending $40 million on the hotel quarantine program in the six months since the multimillion dollar complex opened.
Deputy Premier Steven Miles said most of that $40 million was used to wind down the hotel quarantine program and pay outstanding invoices to participating hotels.
Another 800-bed facility, worth $350-400 million, is being jointly built by the state and federal governments at Pinkenba, near Brisbane Airport.
