In China, he cultivated a powerful senior intelligence officer who had access to embarrassing information about top government bureaucrats. He fled China in 2015 after the patron, Ma Jian, a vice minister for state security, was detained.
While in China, Mr. Guo met many celebrated Americans, including Henry Kissinger and George P. Shultz, both former secretaries of state. When he submitted his application to the co-op board of the Sherry Netherland Hotel on Fifth Avenue for a $68 million penthouse apartment, he included a letter of recommendation from Tony Blair, the former British prime minister. “Miles is honest, forthright and has impeccable taste,” Mr. Blair wrote.
Born into poverty in rural China, Mr. Guo, whose current age has been variously characterized as 53 to 56, developed a refined style, preferring tailored Brioni suits and luxury cars. When Federal Bureau of Investigation agents raided his properties last year, they found two mattresses worth $36,000 each, a $31,000 bed, a $140,000 piano and several cars, including a Bugatti Chiron Super Sport, a Lamborghini and a Rolls-Royce.
In exile, Mr. Guo mounted a campaign in 2017 to discredit China’s anticorruption chief ahead of an important Communist Party meeting that fall. In doing so, he built up a large following of supporters both within China and among the vast Chinese diaspora, though his claims about corruption in the top ranks of the Communist Party couldn’t be substantiated by The New York Times.
That same year, the Chinese government mounted an unsuccessful campaign to repatriate Mr. Guo, tapping Steve Wynn, the finance chairman of the Republican National Committee who ran a casino resort in the Chinese territory of Macau, along with Elliott Broidy, the deputy chairman, to persuade Mr. Trump.