George Mandlazi, 32, was driving the truck when it collided with a coal train between Hectorspruit and Malalane on Friday morning. He was arrested after being discharged from Rob Ferreira Hospital in Mbombela that evening.
His charges were reduced from murder to culpable homicide when he appeared in court.
The case was postponed to Tuesday when he will apply for bail in the Barberton Magistrate's Court, said provincial police spokesman Colonel Leonard Hlathi.
Also on Monday, Public Enterprise Minister Malusi Gigaba met with the victims' families in Mdladla village near Malalane. He was accompanied by Mpumalanga Premier David Mabuza, Deputy Minister of Transport Sindi Chikunga, Transnet managers and Road Accident Fund officials.
"It's a terrible tragedy for the nation. That's why the President (Jacob Zuma) sent us to help them by any means. These families are very poor. Help is underway for them, for the burial, food and more as all spheres of government jointly come forward with help," said Gigaba.
Premier Mabuza urged the police to investigate the case thoroughly.
"We hope police will help us get to the bottom of the cause of the accident and that all those involved are charged and sentenced," said Mabuza.
CEO of Transnet Freight Rail, Siyabonga Gama, said Transnet would also work with government to ensure the victims received a dignified burial.
At about 7:45am on Friday, 45 farmworkers were travelling in an enclosed truck to Tulloh citrus farm when a coal train slammed into them at railway crossing. They were on their way to harvest oranges.
Nineteen people died on the scene and another six died either while being transported or at hospital.
A memorial service will be held on Thursday while a mass funeral service will take place at KaMhlushwa stadium on Saturday.
