According to local media, the eight people detained for questioning on Tuesday were employees of Nana Backpackers Hostel, where all the victims stayed.
The owner of the now-closed hostel has previously denied selling illegal alcohol.
Speaking at Melbourne Airport, Prime Minister Jones urged the Laotian government to continue to pursue the case, adding that the families involved would work to “raise awareness of methanol poisoning”.
The remaining four victims were identified as Simone White, a 28-year-old lawyer from England. James Louis Hutson, a 57-year-old American; Danish citizens Anne-Sofie Orkild Coyman, 20, and Freja Vennervald Sorensen, 21.
Mr Hutson was found dead in his hostel bedroom on November 13 with several empty glasses lying nearby. The same morning, Orkild Coyman and Vennervald Sorensen were also found unconscious in their room and taken to a nearby hospital.
It is unclear how many people have become ill due to suspected poisoning, and investigations into the deaths continue.
The hostel manager was among several people questioned by police last week. He previously told The Associated Press that Jones and Bowles were the only tourists staying at the location who became unwell after drinking free alcohol before heading out for the night.
Commonly found in industrial and household products such as paint thinner, methanol is a colorless chemical sometimes used in bootleg alcohol.
Ingestion of just 25 milliliters (about half a pill) can be fatal, but it can take up to 24 hours for victims to show signs of illness through symptoms such as vomiting and abdominal pain.
Methanol poisoning has long been a problem across Southeast Asia, particularly in poor countries along the Mekong River, with the wider region having the highest incidence of incidents globally.
The recent surge in deaths has put the notorious party city of Vang Vieng in the spotlight and prompted new warnings from governments around the world about drinking in Laos.
