Here's a good article about how fake it was (apologies for the semitic surname of the writer). I'll copy some of the best parts.
https://www.cnn.com/2021/11/18/politics/steele-dossier-reckoning/index.html
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The indictment also says the dossier contained a relatively mundane item about Trump campaign infighting that Dolan later told the FBI he actually gleaned from news articles. Prosecutors say Dolan even lied to Danchenko about where he got the gossip, by attributing it to a "GOP friend" who was "a close associate of Trump."
(anon sources...DERP!)
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While Steele was passing his tips onto the FBI in fall 2016, a Clinton campaign lawyer separately met with a senior FBI official and gave him information about strange cyberactivity between servers at the Trump Organization and Alfa Bank, the largest private bank in Russia.
The lawyer, Michael Sussmann, has since been charged with lying to the FBI during that meeting, for allegedly saying he wasn't providing the dirt on behalf of any client, even though he ultimately billed that time to the Clinton campaign, and also billed them for other work he did on the server issue. Durham says Sussmann repeated this lie during a meeting with CIA officials in February 2017, where he told them about the server theory. Sussmann has pleaded not guilty.
The indictment says Sussman peddled the same material to a Slate reporter, who published a story right before the election. The story said reputable computer scientists uncovered unusual activity between servers belonging to the Trump Organization and the Moscow-based Alfa Bank, suggesting a secret backchannel.
The Trump Organization and Alfa Bank both denied there was a backchannel. The FBI investigated the underlying data and ruled out any improper cyber links by February 2017.
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For starters, we now know that Steele's primary source, Danchenko, wasn't some deep-cover Kremlin insider. He was a DC-based think tank analyst with a Rolodex of Russians.
The FBI tracked down Danchenko and interviewed him a few times in 2017 while they scrambled to verify the dossier. Danchenko said the information he gave to Steele was mostly "hearsay," "just talk," "word of mouth," and came from "conversations he had with friends over beers." Danchenko also said Steele puffed up the memos and leaned too hard into the raw information he received, according to a bombshell 2019 report from Justice Department inspector general Michael Horowitz about the Russia probe.
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In interviews with the FBI, Danchenko attributed the information to Sergei Millian, a Belarusian-American businessman who did some real estate work with the Trump Organization. The indictment also says Danchenko sourced the "pee tape" story, in part, to Millian. But Millian wasn't the source, Durham says, contradicting press reports from 2017. (Some outlets recently corrected or clarified those reports.)
Millian has since said he was "framed" by Danchenko and has publicly denied that they ever spoke, though there is no indication in the indictment that Millian ever denied it to the FBI or under oath.
"This fraud destroyed my health, life, businesses and turned my American dream into (a) nightmare," Millian told CNN in a statement, declining further comment.
A bipartisan Senate Intelligence Committee report released last year said Millian's behavior during the 2016 election "resembles activities by a Russian intelligence officer or cooptee." He has vehemently denied working for the Russian government.
Another Russian who Danchenko told the FBI was one of his sources said in a sworn affidavit in a civil case that she wasn't the source for at least one claim that was attributed to her. The woman, publicist Olga Galkina, said she believes Danchenko told the FBI she was his source "to create more authoritativeness for his work," according to court filings.
The indictment against Danchenko quotes emails where Galkina told Dolan she is a "big Hillary fan," and hoped to land a job at the State Department after Clinton became president.
Taken together, these revelations about Dolan, Millian and Galkina raise grave questions about where Danchenko got his information, or if he perhaps made some of it up.
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It took five years of criminal investigations, civil cases and congressional reports to pull back the curtain on the flimsiness of the dossier. The big picture really came into focus in 2019 with the release of a Justice Department watchdog report.
That report described for the first time Danchenko's many walk-backs in his FBI interviews. It also said FBI agents gave Steele mixed reviews, with some seeing him as a "person of integrity," while others said he had a "lack of self-awareness" and was "underpinned by poor judgment," even if he was acting in good faith.
The report also said the CIA viewed Steele's material as an "Internet rumor."
Last year's bipartisan Senate report said "the tradecraft reflected in the dossier is generally poor relative to (US intelligence community) standards."
The blockbuster 966-page report also raised concerns that some of the material Steele put in his memos was Russian disinformation.
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The FBI included snippets of Steele's reporting in the FISA application, along with other information, like details of Page's previous interactions with Russian spies, and the fact that he suggested to an FBI informant that he had an "open checkbook" from the Kremlin. The secretive FISA court approved the warrant in October 2016, as well as three subsequent renewal requests, meaning Page was wiretapped for about one year.
{yellow]In April 2017, CNN was first to report that the FBI included some material from the dossier in the FISA applications. The article said prosecutors would only have done this "after the FBI had corroborated the information through its own investigation," according to officials familiar with the process.
It's now clear that this level of verification never materialized. The watchdog report said Steele's claims about Page "remained uncorroborated" when the wiretaps ended in 2017.