If you have previously recommended this thread, you should see a tick / check mark on the recommend button. Click the tick to undo the recommendation (the tick may appear to change to a cross as you do this.) If you added a comment with your recommendation, you will need to delete that from your facebook wall separately.
I think your ds is quite young, isn't he? There is no real rush. Why don't you take your time and find the teacher you are really comfortable with for him? You could tell this teacher that you thought the trial lesson went very well but you are undecided atm and can you get back to her in the new year?
Keep asking around for recommendations, if that is what you want to go on. Maybe try and find another teacher for a comparison at least.