Catalysis of the reaction: 1-O-(4-hydroxy-3-methoxybenzoyl)-beta-D-glucose + cyanidin 3-O-beta-D-glucoside = cyanidin 3,7-di-O-beta-D-glucoside + vanillate.
cyanidin 3-O-glucoside 7-O-glucosyltransferase (vanilloyl-glucose dependent) activity