Entertainment reporter Peter Ford told Nine’s The Morning Show that the Australian Idol winner's illness was a rare gene mutation, requiring him to have his stomach removed.
“If he hadn’t got his stomach removed he would have almost certainly gotten cancer,” said Ford.
A documentary airing in New Zealand, Stan, will reveal more on the singer's mystery illness.
In a trailer shared on his Instagram an emotional walker is seen preparing for surgery.
“What if there’s complications, then that’s how I die," he says.