Cambodia lacks the mental health facilities to cope with the deep trauma of refugees on Nauru, a whistleblower has said in the wake of horrors and abuse laid bare in the leaked “Nauru Files”.

Jane – which is a pseudonym to protect the source’s identity – lived and worked in child protection both in Cambodia and Nauru, and was among more than 100 former workers to go public this week.

“I couldn’t live with myself if I stayed silent,” she said.

Jane worked on Nauru for Save the Children between May 2014 and April 2015 – just before the first four refugees were transferred to Cambodia under Australia’s controversial A$55 million scheme.

“Therapeutic trauma services are few and far between, and the people I worked with in Nauru have lived through a great deal of trauma, which caused them to flee and then in their detention and uncertainty on Nauru,” she said. “I couldn’t see the services available coping. Some of the children especially are likely to need counselling through childhood and into their adult lives.”

Some of the women she worked with on Nauru had been raped – by both guards and fellow refugees. “This was going on behind 10-foot-high, anti-climb fencing that people were not allowed to leave. They were, and some continue to be, trapped with their abusers.”

Jane said the reason such a small number of refugees had taken up the Cambodia deal was likely due to the deep distrust of Australia’s promises.

“Asylum seekers and refugees told us they had been transferred from Christmas Island to Nauru with the promise from [the Department of Immigration and Border Protection] that they would be processed and settled faster, that they were lucky to go to Nauru,” she said.

“When [former Australian immigration minister] Scott Morrison was shown in videos stating they would never come to Australia, any remaining hope or glimmer of trust was quashed. They feel they were intentionally deceived . . . How could they trust any information they heard about Cambodia?”

She said Cambodia information sessions on Nauru were boycotted and Khmer-language classes were offered to staff instead as there was sparse interest from refugees – however, of the 10 families with which she worked, about half had asked about Cambodia.

The Nauru Files revealed several refugees were distressed by the Cambodia deal to the point of contemplating suicide. “When they Googled Cambodia, they were met with images, video and information about genocide. For many, this reminded them of the persecution they had fled,” Jane said.

Enticements – such as speedy processing of asylum claims, were offered to refugees who took the deal, while rumours circulated that houses and cars would be purchased for them.

“What people want, though, is the guarantee of a safe and stable future, and that couldn’t be given,” she said.

Jane’s concerns were echoed by Jesuit Refugee Service director Denise Coghlan, whose 23 years in Cambodia showed her that “very few” refugees ultimately stay.

“Mental health services in Cambodia are stretched to capacity to cater for the Cambodian population,” Coghlan said, adding she had informed Australian officials before the deal was inked that they should not be “fobbing off” refugees in their care to less-wealthy countries.

While Coghlan welcomed this week’s news that the Manus Island detention centre in Papua New Guinea would be shuttered, it was “high time Australia accepted its moral obligation to the people on Manus and Nauru and stopped acting as cowards who say it is the fault and responsibility of someone else”.

Kerm Sarin of the Department of Immigration said it was up to NGOs to provide “extra services” to refugees, not his department. “We are only responsible for the paperwork,” he said.

He added that Australia had as yet not contacted his department about resettling refugees from Manus Island.

A spokesman at the Australian Immigration Department said he could not respond by press time.