There is no advise for her without 1) leaving the cult 2) filling divorce on her own term 3) with a knowledge that she will be shunned forever.
You have to understand that with WT there is no compromise or middle ground. If she remains with WT even after possible divorce, her life and your with it will revolve around KH, WT, and everything. You will not have easy and happy marriage. The advice I said and other too, said it all. Run. It is like a person from free western democracy decides to move into communist regime like USSR, and hoping he can enjoy the sight, while maintaining his or her western freedom. Impossible combination.