Jennifer Williams, aged 31, assisted in the conviction of five men, including a disgraced police officer.
Williams, of Furlong Close, had faced a four-and-a-half term in prison after pleading guilty at Warwick Crown Court to conspiring to manage a brothel and conspiring to supply cocaine.
But unlike her co-conspirators, who were all jailed last month, she was given an 18-month prison sentence suspended for 18 months, with 18 months supervision.
The court had heard Williams was working at a sauna in Birmingham in 2012 but she then travelled to London's West End in March of that year to coincide with the build-up to the Olympics to work as a 'a working girl' in Bentinck Street. The brothel got clients through taxi drivers who would get paid £150 cash for each person they would bring to the house.
Williams was shown a document recovered from co-conspirator Atif Hussain's home in Birmingham, and explained that it was a list she had made of what the girls had earned for their hours worked and what quantities of cocaine had been sold.
West Midlands Police officer Pc Osman Iqbal, aged 36, and three Birmingham brothers, Talib Hussain, 36, Atif Hussain, 26, and Asri Hussain, 24, had pleaded guilty to the same charges as Williams as well as money laundering.
Judge Sylvia de Bertodano told Williams: "You made a very significant contribution to the prosecution of this case. Coming to court and giving evidence while those men were in the dock took considerable courage."
Last month Talib Hussain of Douglas Avenue, Hodge Hill, Birmingham, who was said to have been in charge of the operation, was jailed for eight years and four months. Iqbal, whose address cannot be given, was jailed for seven years and two months. Atif Hussain, 27, of Silver Birch Close, Saltley, for four years and two months and Asri Hussain, 25, of the same address, for three years – consecutive to a ten-year sentence he received in August for conspiracy to commit robberies.
Raheela Ali, 44, of Ilford Essex was jailed for 12 months for conspiring to run a brothel and launder the proceeds. Her husband Nassar Ali, 50, was put behind bars for 21 months for the brothel conspiracy and conspiring to launder money.