Labor, the Greens and Centre Alliance each submitted dissenting reports opposed to the medevac repeal bill.
A Senate committee has recommended refugee medical transfer laws be scrapped, despite the majority of evidence submitted to its inquiry backing the process.
The government-dominated committee handed down its final report on Friday finding the so-called medevac laws contained "significant flaws", including the absence of a process for returning refugees to Nauru and Papua New Guinea once they've recovered and short timeframes to assess security and character concerns.
Chaired by Liberal Senator Amanda Stoker, the committee also noted concerns about the strict grounds available to the home affairs minister to refuse transfers on national security grounds.
"The committee understands the minister has already been forced to approve the transfer of six individuals who were 'of security or character concern' because the concerns did not meet the strict grounds upon which the minister may refuse a transfer under the provisions," the report states.
Key crossbench Senator Jacqui Lambie has said she will carefully consider the report before making up her mind on the government's push to unwind the medevac legislation passed against its wishes in February.
With Labor, the Greens and Centre Alliance standing by the changes, the government needs the Tasmanian senator's support to pass its repeal bill.
The Labor, Greens and Centre Alliance senators on the committee wrote dissenting reports supporting the medevac laws which give doctors more say on the transfer of sick refugees from Nauru and Papua New Guinea and accompanying family members.
Labor senators Kim Carr and Anthony Chisholm's dissenting report noted the operation of medevac had shown it was possible to maintain a strict border protection regime without resorting to cruelty.
"When the provisions were introduced, the government claimed that they were a green light to people smugglers and would result in a new surge of boat arrivals. That has not happened," the report states.
More than 130 people have been brought to Australia under the new laws.
Centre Alliance Senator Rex Patrick said the evidence provided during the inquiry demonstrated the new medical transfers system was working as intended.
In his dissenting report, Greens Senator Nick McKim said previous arrangements had resulted in sick people in offshore detention being refused transfers resulting in death, mental anguish and "untold suffering".
Earlier on Friday, Prime Minister Scott Morrison said it was vital to repeal the laws.
"There is this naivety that you can change the rules and they think it won't have any impact - well, of course, it will," he told 2GB radio on Friday.
"The thing about border protection is you've got to be consistent, you've got to be clear, and you've got to hold the line.
"The minute you show that you're prepared to crack it, well, that's when you start losing and Australia can't afford to lose on border protection."
On Wednesday, Home Affairs Minister Peter Dutton used his powers under the medevac laws to block the transfer of an Iranian father to support his 21-year-old daughter who required psychological treatment in Australia.
Additional reporting by AAP