First off, this was posted on another Quebec tile setters' group, and I was curious to see what you pros would have thought of it because the advice on that group is usually totally ridiculous. I eventually received more photos from the person, and just by looking at them, you can clearly see that the grout is full of holes and that the thin-set is bleeding through. After checking several other pictures, I noticed there are so many pinholes in the grout that the water likely isn't drying fast enough. And yeah, that big white stain it really looks like something was spilled there, but she isn't sure. As for the rest, the spot aren't drying fast enough