Daniel,
I'm sorry this is happening to you. You said, "My wife said she will sue for sole custoday without visitation. I'm sure the courts won't uphold that. But it still hurts." - I know it might be an emotional time for you, but given she has said this, perhaps you should re-consider moving out of the house. If you leave the house, that is, officially move out, the courts may view this negatively, as they look toward the child's best interest - which is usually status quo, or whoever remains in the residence.
Tell your wife that you love her, but you also love your son, and you don't feel that it is being exposed to the Watchtower is what is causing your wife the extreme stress.
I mean, you can tell me to go to hell too... I would understand, but I'm just saying that right now its an emotional time for you. By standing your ground, you may be able to keep your son from being a JW, and your wife may be forced to face the real demons - the WTB&TS ... not you..
MeanMrMustard