Craig Stockdale was one of the first St John ambulance officers at the mosque after the mass shooting during Friday prayers on March 15 in 2019. Another mosque in Linwood was also targeted.
In all, 51 people lost their lives and a further 40 were injured.
He became emotional answering questions at an inquest today about potentially life-saving treatments for injured people at Al Noor in Deans Avenue, saying they would not be carried out in a mass casualty situation because of the skill and time involved.
"In my heart I knew what these people needed was a surgeon - not a paramedic on the periphery trying to help them," he said.
"They needed a hospital and we as a group, we knew that and that was our sole aim."
Stockdale said the mosque's hallway was "littered" with bodies and paramedics had to step over people to help those who had survived.
The Coroners Court earlier heard a senior policeman watching a delayed feed of the terrorist's livestream of the massacre relayed the information in error in a panicked transmission over police radio.
For a few minutes, police and paramedics at the scene thought the terrorist was returning to the mosque, but they soon realised it was a mistake.
It was one of the times where Stockdale felt the security situation at the scene changed.
Stockdale told the court police at the scene did not tell him the information was incorrect, which was "unsettling".
There was no debrief about the situation and they all "just ploughed on".
Just minutes later at 2.15pm, the first two St John paramedics entered the mosque with an armed police escort to assess the situation.
Soon after, injured survivors began being taken from the mosque, but Stockdale said he "absolutely" still believed the gunman might come back.
He said if he had been told it was a false alarm, it may have reduced his concern.
