I don't know about the WSO withdrawing membership, but I remember when I first came to Alanon, the only recovery book I had was the Big Book I got when my kids went to rehab.
We didn't read from it, and a woman (who later became my sponsor) mentioned after the meeting that Alanon did not consider the Big Book to be "conference approved literature". That same woman, when she became my sponsor, told me that we would be working from the Big Book from time to time.... just not during the meetings.
The women from my home group have some study meeting outside the regular Alanon group. We have used the Big Book and some other books (Mary Pearl's relationship traditions is one) that we find very helpful.
I figure most things that "need" to happen... do happen. In the right time. So I don't worry overmuch if the WSO is conservative in some areas.
Welcome to SR!!!