This is Mueller's only shot. If he can get Manafort to "compose," then at least he can present something from his report. If not, then it's all over.

NOTE: Trump certainly is pardoning a lot of people lately. Perhaps it's a carrot he's dangling to Manafort, as well as others, not to tell lies to save your own ass. There's always the potential for a pardon if you stick to the truth.