On 23 March 2017, an assortment of left-leaning political web sites, including Occupy Democrats and the Palmer Report, published articles reporting that Russian dissident Denis Voronenkov, who was shot dead earlier that same day in Ukraine, was to have been a "star witness" in a treason trial involving former Trump campaign manager Paul Manafort:
Yesterday, documents surfaced showing that former Trump Campaign Chair Paul Manafort had received at least $750,000 in illegal payments from former Ukrainian President Victor Yanukovych, who is about to be tried for treason in absentia in Ukraine.
Today, Denis Voronenkov was shot to death in the streets of Kiev in broad daylight, just a few weeks after he said he would testify against Yanukovych and his cohorts — Manafort included.
This is only the latest in a list of Russian dissidents to be murdered or die under mysterious circumstances since the U.S. Election. The timing of Voronenkov’s murder in conjunction with the latest revelations about Manafort — a man he was likely to incriminate — makes this latest tragedy all the more suspect.
The clear implication was that the purpose of the killing may have been (at least in part) to prevent Voronenkov, a former member of Russia's parliament and Putin critic who fled to Ukraine, from incriminating Manafort at Yanukovych's trial, scheduled to take place in March 2017.
Mainstream news outlets such as CNN had reported that Voronenkov was indeed cooperating with Ukrainian prosecutors and would be a "key witness" against Yanukovych.
However, we have encountered no evidence that Voronenkov planned to testify about Paul Manafort in any respect. In fact, Voronenkov stated as recently as February 2017 that he knew nothing about Manafort.
As previously reported, Manafort resigned after serving five months as Donald Trump's campaign manager in August 2016 after handwritten ledgers published in the New York Times indicated he had received $12.7 million in "illegal" cash payments (according to Ukrainian anti-corruption investigators) from Victor Yanukovych's Moscow-backed political party between 2007 and 2012. Although Manafort denied receiving such payments, he stepped down from the Trump organization at a moment when it was combating general allegations about ties between the campaign and Russia (as of this writing, those alleged ties are still the subject of an FBI investigation).
Even so, any imputation of a link between the shooting of Denis Voronenkov and Manafort's dealings with Victor Yanukovych is purely speculative, and indeed contradicts Voronenkov's own public statements in that regard.