That really is poor work. If you have paid a pro that much the room should look amazing from every angle, not just from a distance.
He has washed the grout of before it has had a chance to dry, as Brian says above this can be sorted, he will need to cut out the grout and re grout over the top to fill the joints in.
9mm Ply is to thin for a floor, it should be min 18mm boil and water proof ply screwed down at a min of 300mm centres. Just be aware that if the grouting on the floor starts to crack, then you are going to start having problems with the floor and the tiler should have made sure that the floor was suitable before starting work.