The lawyer of former U.S. Marine Paul Whelan said she was unable to confirm the whereabouts of her client after receiving multiple requests from journalists amid growing speculation that Russia is preparing a prisoner exchange with the West. “I had asked the prison’s administration, but they’re not responding,” lawyer Olga Karlova was quoted as saying by the state-run Interfax news agency. Whelan, 54, was working in security for a U.S. vehicle parts company when he was arrested in Moscow in 2018. He is serving a 16-year sentence for spying, a charge the U.S. government says is without merit. W…