The boy was taken to Toowomba Hospital before being transferred to Brisbane, where he died on Monday.
Inflatable World Toowomba released a statement on Tuesday, saying they were “devastated”.
“Inflatable World notified Worksafe on Sunday and they began investigating. A full investigation involving all relevant authorities is underway, we have also undertaken our own internal investigation, are working with authorities and have passed on our findings.
"Inflatable World takes the health and safety of our patrons, staff and others very seriously while they are on our site and have taken extensive measures to ensure we have the highest standards for workplace safety.
"We offer our deepest condolences to the family.”