Hi. Our contractor did a great bathroom remodel for us with marble tile floors. However 2 days after he finished the toilet valve leaked and caused water to get under the tiles. Since it was white marble we could see where it was moist/wet because it was more grey where wet. He insisted it would dry out on its own. but i insisted he remove some of the tiles and replace. however he did not replace some of them and I notice that a few still have that grey color, do you think that will dry out under the tile over time? should i be concerned that mold can grow under the tile?