Some people are invested emotionally, politically, and career-ally in said denial. I am curious how many of them will have the humility to admit they were wrong. Sadly, this has become my only metric for the quality of public servants: Can they admit it when they are wrong? Do they offer to change, or do they just blame others for their failures? I assume none of them have this capacity until I see it. The "lab leak" story will offer an opportunity for us to observe a large number of public servants either admit their mistakes ... or not.

At this point I need verification of sources to believe any claims at all.

 That's fair and my high confidence comes from actually reading a lot of the primary sources and not just media reports. 

When it comes to this claim in particular, let's look at the primary sources.

The bill requires them to:

Not later than 90 days after the date of the enactment of this Act, the Director of National Intelligence shall—
(1) declassify any and all information relating to potential links between the Wuhan Institute of Virology and the origin of the Coronavirus Disease 2019 (COVID–19), including—
(A) activities performed by the Wuhan Institute of Virology with or on behalf of the People's Liberation Army;
(B) coronavirus research or other related activities performed at the Wuhan Institute of Virology prior to the outbreak of COVID–19; and
(C) researchers at the Wuhan Institute of Virology who fell ill in autumn 2019, including for any such researcher—
(i) the researcher's name;
(ii) the researcher's symptoms;
(iii) the date of the onset of the researcher's symptoms;
(iv) the researcher's role at the Wuhan Institute of Virology;
(v) whether the researcher was involved with or exposed to coronavirus research at the Wuhan Institute of Virology;
(vi) whether the researcher visited a hospital while they were ill; and
(vii) a description of any other actions taken by the researcher that may suggest they were experiencing a serious illness at the time.

(2) submit to Congress an unclassified report that contains—
(A) all of the information described under paragraph (1); and
(B) only such redactions as the Director determines necessary to protect sources and methods.

The report that they released says:

(U) WIV RESEARCHERS WHO FELL ILL IN FALL 2019
Several WIV researchers were ill in Fall 2019 with symptoms;
some of their symptoms were consistent with but not diagnostic of COVID-19. The IC continues
to assess that this information neither supports nor refutes either hypothesis of the pandemic’s
origins because the researchers’ symptoms could have been caused by a number of diseases and
some of the symptoms were not consistent with COVID-19. Consistent with standard practices,
those researchers likely completed annual health exams as part of their duties in a highcontainment biosafety laboratory. The IC assesses that the WIV maintains blood samples and
health records of all of their laboratory personnel—which are standard procedures in highcontainment laboratories.
• We have no indications that any of these researchers were hospitalized because of the symptoms consistent with COVID-19. One researcher may have been hospitalized in this timeframe for treatment of a non-respiratory medical condition.
• China’s National Security Commission investigated the WIV in early 2020 and took blood samples from WIV researchers. According to the World Health Organization's March 2021 public report, WIV officials including Shi Zhengli—who leads the WIV laboratory group that conducts coronavirus research—stated lab employee samples all tested negative for SARS-CoV-2 antibodies.
While several WIV researchers fell mildly ill in Fall 2019, they experienced a range of symptoms consistent with colds or allergies with accompanying symptoms typically not associated with COVID-19, and some of them were confirmed to have been sick with other illnesses unrelated to COVID-19. While some of these researchers had historically conducted research into animal respiratory viruses, we are unable to confirm if any of them handled live viruses in the work they performed prior to falling ill. 

You can tell for yourself whether you believe they reported here what the law required them. I think it's very clear that they didn't follow the law and withheld information. 

If the person that fact check employed would have been half decent at their job, they should know that not including the details that the law asked for was a violation in the law but they failed to inform their readers about that fact. 

And given the previous reporting of the IC leadership overruling their analysts when the analysts believed in the lab leak the fact that the IC leadership is illegally withholding information matters.