Auden Karlsen, 28, claims he was a prisoner at the Culture Club star's home in Shoreditch.
He said he met George on the website Gaydar but only went to the flat as a photographic model.
He said George and another man held him at the property after taking pictures.
The star allegedly produced whips and sex toys and threatened him.
Mr Karlsen said he only escaped after wrenching a hook out the wall.
George, charged under his real name of O'Dowd, denied the allegations when they came to light in April. He could be jailed for life if he is convicted.
Last year George was given community service in New York after pleading guilty to falsely reporting a burglary at his Manhattan flat.
The officers who responded found traces of cocaine there instead.
He was ordered to clean the streets for the city's sanitation department as part of his community service and forced to wear an orange workman's bib.
The star, who has admitted heroin addiction in the past, vowed never to return to America but said it had helped him to bring stability to his chaotic lifestyle.
"The media has this image of me as this big faggot sitting on cushions all day eating grapes. But I'm a real person, I have a Hoover, I don't have a cleaner.
"So the idea that I can't pick up a broom and shovel is ridiculous. The hard work was good for me. You just get on with it."
source: Dailymail
