He's been held in solitary for his own protection, because he's a high profile inmate, and could possibly be targeted by other inmates who are looking to make a name for themselves.
And, while he is being transferred to Rikers, he's still going to be in solitary, and will be held in a wing that also houses other high profile inmates like police officers, high profile murderers, and cop killers.
Lots of upset over nothing.
Here.......................if anyone wants to read about it, here's another link that is a bit more informative.
Paul Manafort to Be Sent to Rikers, Where He Will be Held in Isolation
Paul J. Manafort, President Trump’s former campaign chairman who is serving a federal prison sentence, is expected to be transferred within the next few weeks to the Rikers Island jail complex in New York City, where he will most likely be held in isolation while facing state fraud charges, people with knowledge of the matter said.
High-profile inmates are generally held in protective custody on Rikers Island, a network of nine jails with a total of 7,500 inmates, including pretrial detainees and convicts serving sentences of a year or less. Inmates in protective custody are isolated from the general population under heavy guard.
A law-enforcement official familiar with the correction department’s practices, speaking on the condition of anonymity to discuss security measures, said Mr. Manafort would most likely be housed in a former prison hospital on the island. That is where most high-profile detainees are held, including police officers, those accused of killing police officers, politicians and celebrities.