An independent expert report found that a 23-year-old man who died at the Defqon.1 music festival last year may have survived if he’d received better care at the event.

Joseph Pham, 23, was one of two young people who died after taking MDMA at the Defqon.1 festival in western Sydney last September.

Along with Diana Nguyen, 21, who also died after attending the event, he is one of the six people whose deaths from MDMA toxicity are being investigated by the New South Wales coroner.

Last week the inquest heard about multiple issues with the medical care provided at some of the festivals and paid particular attention to the service provider EMS, which was employed at Defqon.1.

The inquest heard the 30,000-person event had only two doctors on staff, including one, Andrew Beshara, who had never independently intubated a patient.

Andrew Beshara, the more junior of the two doctors working in the festival’s medical tent. Photograph: Joel Carrett/AAP

Pham was taken to hospital almost an hour after a doctor said he needed an ambulance, while a NSW Ambulance paramedic who worked at the event described the care provided by EMS as “completely abhorrent”.

And an expert report prepared by the emergency medicine specialist Associate Professor Anna Holdgate found that Pham may not have died if EMS staff had transferred him to hospital sooner.

“In my opinion, if Joseph had received immediate treatment to lower his body temperature and had been promptly transported to hospital by appropriately skilled NSW Ambulance intensive-care paramedics, he would have arrived at hospital prior to his cardiac arrest and may have been effectively resuscitated,” Holdgate wrote in her report.

“While it is by no means certain that this would have prevented the fatal outcome, it would certainly have significantly improved his chances of survival.”

Diana Nguyen, 21, died from MDMA toxicity after attending the Defqon.1 festival.

Both Pham and Nguyen presented separately at the festival’s medical tent within only a few minutes of each other.

Pham, who had taken an “unknown number of pills”, was unconscious with an elevated heart rate, while Nguyen, who had taken two pills, was unconscious, “extremely hyperthermic” with low oxygen levels and profusely sweating.

With only two doctors at the event, the inquest heard last week that the more senior of the two, Sean Wing, made the decision to prioritise the care of Nguyen who he believed to be in a more dire situation.

Pham’s care was left to NSW Ambulance paramedics and the more junior doctor, Beshara.

Last week Beshara gave evidence to the inquest that he had asked for Pham to be transported to hospital sooner, and admitted staff at the event felt “overwhelmed” by the situation.

“His jaw was essentially wired shut, his arms and legs were tensed up and he was very stiff,” Beshara told the court. “Essentially from the moment we received him, he would need to be transferred.”

He said he told the EMS director Michael Hammond that Pham needed to be transferred to hospital soon after the arrival of Nguyen.

“It’s a statement I expressed loudly,” he said.

Holdgate said in her report that at the time of Pham’s presentation at the medical tent he had “signs of significant MDMA toxicity” and that it was clear he would need to be transported to hospital.

“However, EMS staff did not initiate a plan to transport him to hospital until after he had progressed to cardiac arrest,” she wrote.

Sean Wing, the more senior of two doctors at Defqon.1, accompanied Diana Nguyen in the ambulance to hospital, believing that leaving the festival was a ‘calculated risk’. Photograph: Peter Rae/AAP

She wrote that initial testing which showed Pham’s body temperature levels was probably wrong, and that “no treatment for hyperthermia was initiated at any stage either pre-hospital or after he arrived at Nepean hospital”.

In her report Holdgate wrote that she had “a number of concerns about the treatment provided by the EMS medical team at the event”.

She said medical staff were “rapidly overwhelmed” by the number of patients and lacked the skill to manage critically ill patients, apparently “rapidly ran out of basic resuscitation equipment” and that medical staff were not adequately skilled to manage critically ill patients.

“The decision-making as to what treatment should be provided on site and when patients should be transferred to hospital was poor,” she wrote.

Wing accompanied Nguyen in the ambulance just after 9pm, leaving Beshara – who had little critical care experience – as “in effect the chief medical officer” of the facility.

“It seems that Dr Wing attempted to treat both patients as if he was in a well-supported hospital environment rather than a relatively isolated facility with limited physical and human resources,” Holdgate wrote.

Last week Wing said he believed Nguyen was dying, and leaving the event with her was a “calculated risk”.

“I felt there was no conceivable alternative in my mind,” he said.