My situation is quite similar to yours, except for the fact that I have never been a JW. My two children are indoctrinated into a religion that I recently discovered is very dishonest and manipulative. Before, I thought it was a good religion. Now that I know TTATT, I refuse to let the deception continue. My children will be enslaved and be asked to sacrifice their dreams for the sake of the whims of few old men. Hell no! Not on my watch!
I don't know what is best for the short term. However, truth is always best in the long haul. If I were a kid (of course with the mind of an adult) and were able to choose, I would ask for the truth.