Communication of plan and strategy that was going on directly with Kilimnik by Gates and Manafort.
The meeting below discussed is in May. https://www.intelligence.senate.gov/sites/default/files/documents/report_volume5.pdf page 80 of the report, 94 of the PDF:
"At the meeting, Manafort walked Kilimnik through the internal polling data from Fabrizio in detail.453 According to Gates, Kilimnik wanted to know how Trump could win.454 Manafort explained his strategy in the battleground states and told Kilimnik about polls that identified voter bases in blue-collar, democratic-leaning states which Trump could swing.455 Manafort said these voters could be reached by Trump on issues like economics, but the Campaign needed to implement a ground game.456 Gates recalled that Manafort further discussed the "battleground" states of Michigan, Wisconsin, Pennsylvania, and Minnesota.457"
It's pretty clear, to me, he was doing what he was doing in order to inflate his value and try to collect on $10mm in owed debts from Ukrainian oligarchs given he was broke. In my opinion, his goal was not "share info in order to influence the election" although I don't think intent matters much here. The Trump campaign literally did zero vetting to understand Manafort's significant liability given his financial situation.
The question is, of course, was Manafort doing this with Trump's knowledge/blessing? I don't think that was ever answered and as I understand it, within a day or 2 of Trump's first national security briefing in August, Manafort was out.