honestly, i'd make the absence of a complete database a plot hook itself.. have a group dedicated to trying to rebuild the database, by collecting the fragments that have been found and cross referencing them (and the various ID codes, file names, indexes, etc) in an attempt to reconstruct it. maybe even learn something of what parts are missing, based on cross-references and fragments.
to which end their founding agencies and individuals might be willing to recruit people to go search for star league relics, or conduct raids into the archives of various IS state entities to copy materials they can't get normally.