"Mother" suggests a theme for Family Worship ... God's Organization - A Worthy Topic for Study
So, how about suggestions for a gradual study that would expose the organization for what it is. How to start it out innocently and move into the stuff that will expose the truth.
Perhaps you suggest a study of the "Proclaimer's" book?
I'm sure there's all sorts of information in that book that can "springboard" the discussion into what things were taught in the past. Then maybe you guys borrow some older books from the hall, if yours has such a library.