I expect the diligent search clause will be all but meaningless. In all likelyhood the agency charged with verifying that a user of the images made a "diligent search" will be grossly underfunded, understaffed and provided a 1995 vintage cast off pc do do the work with.
Those with solicitors on-staff will come up with myriad reasons that googling the image's file name constitutes a "diligent search", and the agency will have no choice but to rubber-stamp the claim.