Plans to reopen Dreamworld for a memorial day on Friday have been thrown into doubt after Queensland Police warned they might not give the park's operators the all-clear.
The park on Wednesday night announced they had planned to open for water and animal attractions to raise money for the Red Cross charity.
But Assistant Commissioner Brian Codd is concerned the reopening might cause problems for the ongoing police investigation.
"We are not going to compromise the speed or thoroughness in order for us to vacate the area and acquire the evidence or facts we need," he said
"Let's be aware of what the implications might be for our ongoing security of the crime scene."
The area around the Thunder River Rapids ride, which malfunctioned in the fatal incident, remains a crime scene.
Police still have a warrant for the park that lasts until at least next Tuesday and can be extended if required.
Mr Codd indicated that would be unlikely, but warned the investigation could still shift to other parts of the theme park.
"If there are perhaps other electrical or water or hydraulic sources, or switches from another part of the park that impact on that ride, they form part of the investigation," he said.
"We're going through this meticulously, in great depth, the scope of this is quite considerable."
However, he said any evidence would be protected if the park was reopened to the public.
"Steps have been taken about securing the scene already to maintain the security of that area."
Premier Annastacia Palaszczuk arrived to lay flowers "on behalf of all Queensland families who cannot be at Dreamworld" at the makeshift memorial established near the entrance of the park.
She refused to be drawn into the debate about when the park should reopen, but instead said she would leave it in the hands of police.
"The issue of Dreamworld reopening tomorrow is a matter between the organisation and police," she said.
"It is up to those parties to make that decision."
Mourners laying tributes outside the park were mixed in their views on whether the park should be available to the public from Friday.
"I thought they would be closed a bit longer than that," regular park-goer Nicole Stokes told AAP as she dropped off flowers.
