They were sentenced to pay a 5,000 ringgit ($1,900) fine and spend three days in jail, which - taking into account the time already in detention - expired at midnight on Friday. They spent Saturday morning with the immigration authorities, before being taken to the airport.
Miss Hawkins' father Tim told The Telegraph that his daughter, who left the UK in January to travel alone throughout South East Asia, had intended to travel onwards from Malaysia to Singapore and Hong Kong. But instead she was flying directly home to Derbyshire.
He said the sentence was "appropriate and fair for the offence committed", and that he was looking forward to welcoming her home.
Her saga began on May 30, when she was climbing Mount Kinabalu - a sacred mountain on the northern tip of Borneo, in Malaysia's Sabah state.
The group of ten dared each other to take their clothes off near the summit, and withstand the chill on top of the 13,435ft-mountain - the tallest peak between the Himalayas and New Guinea.
But when photos of the prank emerged on social media, a formal complaint was made. Miss Hawkins and the other three were arrested on Tuesday, remanded in custody on Wednesday, and sentenced on Friday evening.
"I'm not surprised at how quickly they processed the case," said Mr Cham. "The important thing is that the embassy and the parents took my advice - to plead guilty and offer an apology.
"This was their best bet."
Mr Cham said that foreigners in Malaysia would not be granted bail, because they needed two local people to provide surety. If they contested the charges, they would have faced "months, even years" awaiting trial, he added.
And he said the group were fortunate to escape prosecution from a native court.
Tribal people in Sabah had threatened to haul the four before their own judge, where they would have faced unspecified jail time or fines. Ten head of buffalo was suggested by one elder as a suitable punishment.
"The native court could have issued a summons," said Mr Cham. "I don't know if they have started a procedure. But the four were lucky to have been released on a Saturday, when the native court wasn't sitting."
All four are in theory entitled to return to Malaysia - although only Mr Snel asked the lawyer whether that was a possibility.
"I'm really happy that they are on their way home," said Mr Cham. "My work is done."