The statement corroborates witness accounts from 101 migrants who said they were promised jobs, only to be tortured and enslaved.
Their alleged captors have since been detained and face hundreds of charges in Vanuatu, including human trafficking.
An IOM spokesperson said the organisation is now providing bi-weekly food rations to the victims - many of whom refuse to return home.
The spokesperson said it's working with Vanuatu's government to assist in a voluntary return of the migrants.
"This process includes medical checks and an assessment of their area of origin to determine their needs in terms of reintegration support when they return."
Collectively, the group is demanding $US1.8 million in compensation for lost work and alleged abuse from Vanuatu or Bangladesh, whoever will pay.
According to a report detailing the men's claims which was provided by a representative last week, just 14 have said they are willing to return home.
"From IOM's side we are encouraged that more of the group now do want to return home - something that both the Vanuatu and Bangladesh governments support," the IOM spokesperson said, declining to provide exact numbers.
The men are being housed in Vanuatu's capital Port Vila under police protection, with the government providing food, water and housing - although some migrants have said that support has been declining because of their refusal to be repatriated.
IOM had previously facilitated funding from New Zealand's High Commission in Vanuatu to provide the men with essential items including hygiene kits and repairs to their water supply.