The blue is darkish, so would dip too with the grey lines between the tiles, if you displace the whole lot. So you should make an RGB file separating the colors you need for the tiles and the displacement, so channel Red could be the soft grey (either make them dark on white or white on black) for the dips, Green the white tiles, and Blue the blue tiles. In TG you use blue nodes convert Red to scalar, Green to scalar and Blue to scalar to use them as masks for displacement or additional color or so.
Or make two files; the blue and white for the tile colors, and a separate greyscale for the dips between.
And repeat X and Y for a complete floor.