The prisoner Robert Levinson referenced by Sara made me dig a little.
Name Robert Levinson in article Q linked to.
Found this interdasting connection on Wiki
In 2009, the then-FBI Director Robert Mueller was kept apprised of the operation to court Oleg Deripaska, a Russian billionaire and chief executive of the Russian state aluminium monopoly Rusal with close business ties in Iran, to help rescue hostage Levinson from Iran. In May 2018 new details emerged about Mueller's 2009 deal with Deripaska. Multiple sources confirmed that Andrew McCabe was one of Deripaska's early FBI contacts. Agents secretly met Deripaska in hotels in Paris, Vienna, Budapest, Hungary, and Washington, convincing him to to spend millions of his own dollars funding the FBI-supervised operation to Levinson. Because of economic sanctions imposed on Iran and other laws, the FBI couldn’t openly spend taxpayer money on the operation.