I confirmed that tract #17031310800, which brings up a location in Cook County, Illinois, is on the webmap, and that that particular tract number does not appear in the Geocoded dBase file (https://www.huduser.gov/portal/datasets/...022CSV.zip). However, the tract number (3108.00, not the full tract number) does show up in the Geocoded dBase file. The corresponding "qtc_id" is 48201310800. If you search for "3108.00" in the HUD list of the QCT's (https://www.huduser.gov/portal/Datasets/...T2022M.PDF), you will get two results, none of which are found in Illinois.
You might try this HUDuser page: https://www.huduser.gov/portal/qct/index.html
You might try this HUDuser page: https://www.huduser.gov/portal/qct/index.html