Hydrolyzes internal endo-beta-galactosyl linkages in keratan sulfate and in various neolacto-type glycosphingolipids, producing sulfated and non-sulfated disaccharides, and glucosylceramides respectivly. Endohydrolysis of (1->4)-beta-D-galactosidic linkages in keratan sulfate. Belongs to the glycosyl hydrolase 16 family.