Sinead McNamara was working as a crew member on the Mayan Queen IV when she died on board the ship early on Friday while it was anchored near Kefalonia.
The boat is owned by Alberto Bailleres, a Mexican billionaire in the mining business with a net worth of $9.6 billion.
All members of Baillères' family had left the ship on Tuesday and only crew remained on the vessel when the death occurred according to the Coast Guard, although at this stage it's not confirmed if Alberto Baillères was on board or not.
Only days before her death, the model was posting snaps for her 18,000 Instagram followers, including shots of the scenic Greek islands and bikini shots aboard the super yacht.
"It was only a few days ago you were messaging me forcing me to come camping with you".
Authorities have taken depositions from the crew as part of their investigation, as well as performing an autopsy on McNamara's body.
Ms McNamara, originally from Port Macquarie in New South Wales, regularly posted pictures of her travels to her Instagram account, where she had more than 12,000 followers.
The Department of Foreign Affairs and Trade is providing consular assistance to the young woman's family.
She had many who loved her: "Our souls were so perfectly aligned we were convinced we were the same person".
Just four days ago, Ms McNamara was 'jet skiing around the most lovely turquoise water in the med, ' she said referring to Mediterranean.
Greek authorities and media have claimed Ms McNamara took her own life.
Friends and family have paid tribute to an Instagram blogger who died in Greece while working on a billionaire's yacht. You're such a gorgeous girl lost way to soon'. Will cherish all our memories.