Mrs Casboult was bleeding and in severe pain and it was later discovered she had a brain bleed and a broken pelvis.
Despite concern about her condition from paramedics and pleading from her family for assistance, she was denied access to emergency ambulance transportation.
This comes as ambulance response and emergency department treatment times continue to miss their targets after more than a decade of Labor Government.
Shadow Minister for Health, Georgie Crozier, said: "This case is an appalling and heartbreaking example of how broken the health system is under the Allan Labor Government.
"There is something deeply wrong when a 91-year-old great-grandmother who requires emergency treatment and care is denied an ambulance and has to be taken to hospital by the family.
"For the Allan Labor Government to dismiss this incident as a routine clinical assessment, refuse to review the case and refuse to acknowledge the serious failings within the health system is shameful.
"Labor can't manage the health system and Victorians are paying the price."
