I'd like to see the letter. I'm not a lawyer, but I was an accountant for twenty-six years. I have some professional understanding of legal matters.
This may well be used to try to legally sever the link between the individual Congregations and JW Org,
I don't think this can be done, at least not with anything like the current configuration of the Witness Organization. As long as money flows up and orders flow down, the link exists, whether or not the WTBS acknowledges it. And, as one of my accounting professors said "the first rule of law is sue somebody with money." I spent fifteen years in three congregations and I can only think of two elders that might have had enough money to make a lawyer interested in suing them.
In other words, playing word games won't shelter the WTBS