The company contracted to provide health services, International Health and Medical Services, told Mr Ahmed firmly that the clinic was not an "accommodation area" and, as such, a bed in the clinic would not be provided.

In correspondence obtained by Fairfax Media, the IHMS health services manager told Mr Ahmed that if he wished to request a room in the area for those suffering mental health issues, he could contact another contractor.

More than 200 detainees at the centre have signed an open letter calling for a royal commission to investigate the circumstances of Mr Ahmed's death on Christmas Eve.

Released on Wednesday, the letter asserts that Mr Ahmed had heart and other health problems for more that six months before his death, but that IHMS "did not care about him and did not provide any treatment for him".

The letter from IHMS sent to Faysal Ahmed. Photo: Supplied

The company has emphatically rejected Mr Ahmed was denied access to medical care, and released a statement on Wednesday saying it was "very concerned with the inaccuracies and misinformation" surrounding the reporting of Mr Ahmed's death.

"He was seen by clinicians and other allied health professionals at the clinic on numerous occasions in the three months preceding his death for multiple issues and his presenting medical issues were assessed, investigated and managed," the statement said.

"The facts and circumstances surrounding his death will be referred to the Queensland Coroner. However, currently available information indicates that Mr Ahmed died from severe head injuries sustained in a fall at the Manus Island Regional Processing Centre on 23 December."

IHMS was extremely proud of the work of its "highly qualified and professional clinicians", whose efforts to stabilise Mr Ahmed and transfer him to Australia were "exemplary".

Fairfax Media has obtained a raft of documents in which Mr Ahmed repeatedly seeks treatment for a range of conditions including chest pains, difficulty in breathing, swollen hands and stomach pains.

In a formal complaint lodged four days before he was told he would not be given a bed at the clinic, he demanded to know why more than 20 visits to the centre's clinic had not produced a diagnosis of his ailments, let alone a treatment plan.

Detainees have asserted that Mr Ahmed went to the clinic two days after his request for a bed was rejected and was told there was nothing wrong with him.

The documents include formal responses from IHMS that suggest the provider considered his problems were more mental than physical. In October, he was told a primary health nurse and doctor had discussed his problems at length and "ways to resolve these issues".

"You were offered to see mental health regarding your sleeplessness, which you refused," the letter said. "We note that you have been attending medication rounds and we advise that you continue to do so."

This is a reference to what detainees regard as a nightly ritual, where they line up to be given medicine to help them sleep.

The letter calling for a royal commission says the detainees believe Mr Ahmed was already dead when he was flown to Australia on Christmas Eve.

"About two years ago another refugee, Hamid Khazaie, died in similar circumstances to Faysal. Also we lost Reza Barati and Hossein Kamil in this prison in a system made and run by the Australian government.

"We are writing this letter to you to request [a] royal commission to fully investigate IHMS, the provider of medical services and its control by Border Force."

The letter asserts that more than 400 of the almost 900 detainees at the centre require emergency medical treatment.

"We wrote that letter under fear and sadness," one of the signatories, Behrouz Boochani, told Fairfax Media. "The people in Manus are really worried about their health, and there is a big question here that who will be next?"

In what may have been the final response to Mr Ahmed's pleas for medical attention, the IHMS health services manager wrote to him on December 19 informing that his request, presumably for a bed in the clinic, had been received.

"We advise that IHMS is not an accommodation area and as such as bed in the clinic will not be provided," the correspondence says.

"If you wish to request a room in the VSRA you need to contact Wilsons Whisky team and they will assist you with this."

Mr Boochani said VSRA is a small room close to the IHMS clinic where people with mental problems are kept for a few days a time. He said the Wilson Whisky team is a section of the security provider that deals with those with mental health issues.

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