In the new filing, Manafort's lawyers argue that he didn't lie so much as forget.
Kilimnik has been charged with working with Manafort to obstruct Mueller's investigation of Russian interference into the 2016 election.
Another revelation that was meant to be kept under wraps was a meeting between Manafort and Mr. Kilimnik in Madrid.
The longtime Republican consultant already faces a possible maximum, 10-year prison sentence in his District of Columbia case under federal guidelines for conspiring to cheat the Internal Revenue Service, violate foreign-lobbying laws and tamper with witnesses. And in a third redaction apparently gone wrong, defense lawyers revealed that Manafort may have greenlighted an unnamed third party to drop his name if that person secured a meeting with President Trump.
Mueller claimed in a November 26 filing that Manafort breached his plea deal and "committed federal crimes by lying to the Federal Bureau of Investigation and the special counsel's office on a variety of subject matters".
"These circumstances weighed heavily on Mr. Manafort's state of mind and on his memory as he was questioned at length", the lawyers wrote.
What remains unknown is whether Trump or others on the campaign were aware that Manafort provided Kilimnik and Deripaska with polling data.
The proposal would involve Russia pulling forces from eastern Ukraine and allow Ukrainian voters decide whether Crimea should be leased to Russia 50 or 100 years, along with lifting sanctions on Russia.
"Manafort "conceded" that he discussed or may have discussed a Ukraine peace plan with Mr. Kilimnik on more than one occasion", his attorneys quote the special counsel as saying, and " "acknowledged" that he and Mr. Kilimnik met while they were both in Madrid". The US and European Union have imposed sanctions on Russian Federation over that move as well as the country's support for separatist rebels in eastern Ukraine.
"It is not surprising at all that Mr Manafort was unable to recall specific details prior to having his recollection refreshed", Manafort's team wrote. It is unclear whether the polling data was related to the briefings for Deripaska.
Court watchers and the judge anticipated that the Manafort team would either push back on Mueller's team's assertions-like they previously indicated they would-or agree not to fight the special counsel as Manafort headed to sentencing.
The filing claims that the first alleged lie by Manafort was "related to a text message from a third-party asking permission to use Mr. Manafort's name as an introduction in the event the third-party met the President", which they argue "did not constitute outreach to the President".
The lack of public response from the Manafort team leaves the case at a cliffhanger following a series of twists - from Manafort being sent to jail, through his conviction at trial and decisions to flip, cooperate with Mueller, then split with the special counsel's office.
Defence lawyers say they don't want a separate hearing before a judge on the lying allegations, but will address them instead during the sentencing process.