dear auntie jane
print out the letter from the un explaining that the wts was an ngo and agreed to promote the un from 1991 until 2001.
also print out the two guardian newspaper articles about their involvement, the first that exposed this and the second, a day later that reported the wts, coincidentily, resigning from the un.
thus prepared you can invite any and all publishers into your home. sit them down with a cup of tea and casually make them aware of the hypocrisy of their governing body and how they are being misled.
if the message only gets through to one of them, you will have done a good thing.