However, the request is being opposed by lawyers representing the state, who argue requiring them to give evidence in person could be re-traumatising.
Six children were killed and three seriously injured when a wind gust lifted the castle and inflatable balls into the air at Hillcrest Primary School on December 16, 2021.
Preparations for an inquest resumed after Rosemary Gamble, the operator of Taz-Zorb which set up the equipment, was found not guilty in June of criminal workplace breaches.
At an administrative hearing on Thursday, coroner Olivia McTaggart said it was her hope the first block of substantive inquest hearings could begin in September.
The start date depended on when expert reports and evidence from the state was finalised, she said.
Several victims' families have requested staff, including the teacher who organised the event on the oval and the school's then-principal, give evidence in person, counsel assisting Maree Norton said
However, this was opposed by the state because they have already provided affidavits and could be re-traumatised by giving evidence in person, she said.
The state is also providing a statement from a senior education department person, she said.
A final decision on the witness list has been deferred and will likely be made at the next administrative hearing on July 24.
Several families also want the scope of the inquest broadened to specifically include examination of the state education department's oversight of Taz-Zorb, Ms Norton said.
An amended draft scope read to the court includes an examination of Chinese company East Inflatables, which supplied the inflatable equipment, and what information and operating manuals it provided to Taz-Zorb.
The scope will be locked in once legal representatives of various parties have the opportunity to make submissions on the draft.
Lawyer representing the department, Gretel Chen, said she didn't foresee any significant opposition to the proposed scope changes.
In the criminal proceedings, it was found Ms Gamble could have taken further steps in relation to the castle's anchorage, but even if she had it would have made no difference to the outcome.
It was ruled the "dust devil" wind event was impossible to predict.
Ms Norton has previously said the coroner is open to making different findings to the criminal ruling.
A permanent memorial is being created for Chace Harrison, Jalailah Jayne-Maree Jones, Zane Mellor, Addison Stewart, Jye Sheehan and Peter Dodt.