OUCH!! I think your wife is either looking for a Witness legal way out of your marriage or else she really thinks you were having more than just a text message friendship with the other girl. Either way go to a real marriage counselor or hire a good divorce attorney.
Don't extricate yourself from the Witnesses until you decide what you want for yourself and your child. If you try the fade route and live close to Witness relatives they will try to convert your child. Can you accept that?
It's up to you what you are willing to loose, and how much of a hippocrite you are willing to be to get there. If you want to stay a Witness do what the elder's want. They only have power if you let them have it.