Why no one mentions Joseph Mifsud?

Joseph Mifsud the original person into the Trump's campaign gossip of Hillary Clinton. He is the person who told or whispered to Papadopoulos... "We have huge dirt on Hillary Clinton." Is missing even from the Muller final report. Why?
Joseph Mifud last seen in Washington
 In reading the old FBI press release, the aforementioned “United States Department of State’s International Visitor Leadership Program,” struck a chord of familiarity. Sure enough, the program is run by the State Department’s Office of International Visitors, which sponsors the Global Ties national conference. The February 8, 2017, Global Ties conference in Washington DC featured Joseph Mifsud as a speaker.

Joseph Mifsud is a Maltese academic, with reportedly high level connections to the Russian government. In 2016, he became involved with George Papadopoulos, an advisor to the Donald Trump presidential campaign, and was later accused of being a link between that campaign and Russia. Wikipedia

Born: 1960 (age 59 years), Malta

Nationality: Maltese

Disappeared: 6 November 2017 (aged 56–57); Rome, Italy

These facts indicate that the DOJ did not inform the FISA court of the FBI interviews with Papadopoulos and Mifsud. But it should have, especially if Mifsud denied Papadopoulos’ claim that the Maltese professor had bragged that the Russians had dirt on Hillary. Or was Mifsud an FBI informant or an asset of a foreign government, and was that instead what the DOJ told the FISA court?