Mired in the prosecutorial equivalent of a blackout period, Special Counsel Robert Mueller and the remaining prosecutors assigned to his detail are said to be preparing their final report on their findings in the probe into whether the Trump Campaign colluded with Russia - a probe that has stretched into a now 18-month odyssey. But lest reports that the imminent conclusion of the Mueller probe have left readers with a wholly unjustified sense of finality, the Hill is back with a piece published Thursday morning reminding us of all the loose ends that have yet to be tied up - including the fact that a grand jury has continued to interview associates of early Trump advisor Roger Stone. But the Stone's fate, and whatever information he may have to offer on Trump, isn't even the most important of these unresolved factors. As the Hill reminds us, we still don't know what Paul Manafort - whose decision to cooperate with investigators was made only two months ago - is telling prosecutors. And given his extensive involvement with the Trump campaign, it's very possible that the scope of the information he is providing stretches beyond Trump. According to the Hill, investigators are looking into the Republican Party's decision to soften certain tenants of its platform pertaining to Russia and its annexation of Crimea. And it's possible that Paul Manafort has the answers they seek. It's also believed that Manafort could provide information on other issues like whether Trump was aware of the infamous June 2016 Trump Tower meeting (this after the president changed his story, saying Donald Trump Jr. may have organized the meeting to obtain opposition research, contradicting the Trumps' initial denials), or whether the campaign had advanced knowledge of the hacks of the DNC and Clinton campaign. While some witnesses, for example, George Papadopoulos, haven't proven all that useful, as far as witnesses go, Manafort is "leaps and bounds" above the others, one expert said. Manafort, who attended the meeting along with Trump Jr. and Jared Kushner, would have been privy to discussions concerning the meeting and could potentially speak to Trump’s knowledge of it. The president claims he had no advanced knowledge of the meeting. "He can talk about the conversations that took place before, during and after," said Seth Waxman, a former federal prosecutor in D.C. "I would put Manafort leaps and bounds above everyone else simply because of the time and effort the government put in to flip him," Waxman said. "When the government goes as hard and as deep on someone like Manafort, it’s because they want him for a purpose and they believe he has very valuable information." Manafort’s value extends beyond his involvement in the Trump Tower affair. Having spent five months as campaign chairman, Manafort could answer questions about the softening of language in the Republican Party’s platform on Ukraine and any possible accords with the Russians. Former federal prosecutors also expect Mueller’s team to question Manafort on whether the campaign had advanced knowledge of Democratic emails hacked by Russia. It appears former Manafort assistant Rick Gates has also provided information ranging beyond his dealings with Manafort. It was not initially clear whether Gates, who also worked on the Trump campaign and later on the transition, was cooperating beyond the Manafort case. However, a recent filing from his attorney suggests he is helping Mueller on other aspects of the investigation. In a motion asking the court to remove Gates’ GPS tracker and lift some of his travel restrictions last week, his attorney, Tom Green, wrote that Gates’ interviews with the special counsel’s team "have been numerous and they continue to this day." Neither Manafort nor Gates have been sentenced, though Manafort will appear in federal court in Virginia on Friday as Judge T.S. Ellis looks to move forward with his sentencing for the bank and tax fraud charges. it's also possible that Mueller may have brought in other cooperators whose identity or identities are not yet known. "Your job as a prosecutor is to go as high up the chain of the organization as you can and prosecute the most culpable people and put an end of their criminal conduct," said Joyce Vance, a former U.S. attorney in Alabama. "He’ll want to keep going so that the people who he prosecutes are the people who are the most responsible for any criminal conduct he uncovers. No prosecutor wants to stop at the midway point, [though] sometimes you have to because you don’t acquire enough evidence to go higher," Vance said. Given the recent shrinking of Mueller's team and his delegations to other federal prosecutors (most notably involving Cohen), it appears that Cohen's probe has continued to wind down. However, that doesn't mean that Mueller doesn't have one more bombshell indictment - perhaps even his biggest yet - still in reserve.