Hi Paul,
since the idmv_vallink_basic shows the user is in two Id Stores and the Ids of the stores are "2" and "4", do you have more than those two Id Stores in your system/MMC?
If you have more than two Id Stores make sure that the pass that writes the user in Initial Load points to the same Id Store that the UI is using. (either select the Id Store name from the drop down in the pass or maintain the SAP Master Id Store constant)
If you have only two Id Stores, can you take a screen shot of the attribute MX_ADMIN_UNIT definition and try also to make the attribute visible on the UI where you can edit the attribute (just to eliminate something in the attribute definition makes the date not visible in the search results, I am guessing here with the UI but have seen stranger stuff over the years and it takes only couple of mins to check).
regards, Tero