In his haste, my DH used a crappy old sealer that was in garage (Tilelab matte sealer & finish)on our new Travertine floors and now they look awful. You can see every stroke he put down as well as any dirt that was on the tile and it even turned the grout dingy. Apparently the sealer was for exterior saltillo-type tiles.

Can we undo the damage? We bought the 511 Impregnator - is there some way to scrub off the old stuff to put down the 511?