Blackjack, not much was actually known about the prisoner, yet everyone who was in the prison knew his name, and the reason for it was simple. Right in the center of the prison, everyone had witnessed him taking on the Warden and attempting to escape.
Many had tried to escape before, and the Warden had quickly dealt with them all. It didn't take much for everyone to quickly figure out that they had no chance against the Warden.
On top of that, the Warden made it quite clear, even if they could make it past her, what were they going to do then? Go past the hundreds of White Rose Agents that were in the base.
Escape was impossible from the Prison, which is why most of those in the prison made it their whole way of life.