Some food for thought. I've thought for some time that Manafort is afraid of Russian retaliation if he flips.
Even though Manafort is facing 25 charges that could easily put him in prison for the rest of his life — and even though the evidence for many if not most of these charges appears quite strong — he’s pleaded not guilty to everything, and has given no public indication he’s considering flipping.
Why? One possible explanation is he just has nothing to flip with. Either he wasn’t involved in collusion or he has nothing on Trump or anybody else Mueller cares about. Alternatively, maybe Manafort is just holding out hope that he can beat the charges. A darker possibility is that, given an apparent series of
Russia-linked assassinations in the West, Manafort fears violent reprisals against himself or his family should he give information implicating Russians.
The trials of Paul Manafort, explained