Maybe Bani knows by now or she will soon find out that JW-repto could not get married because of the 5 year waiting clause. The first thing she will do is to make sure this marraige does not happen as she in under the impression that the whold drama with her happened because JW-repto want to be together.
By some business manouvers she and AD will bring a situation where WGI can be saved only by a marraige between Durga and JW. To keep her identity hidden she cannot show any initiative about marraige or getting the kids in front of the GFN's and repto. The initiative will be made to come from the Walia clan to stop themselves from being thrown out on the streets.
Once she infiltrates into WM she will be able to see the state of things and then start her revenge on the 3 witches for which she has to be in control of WM as its malkin.
Just my 2 cents................
Pinky that seems like a very probable throry. But why would she agree to a marriage to save the walia's . i mean bani would to get the kids but why would the walia's think that durga would want to marry JW if she can get all their property anyway/