W 81 9/15 Or, a person might renounce his place in the Christian congregation by his actions, such as by becoming part of an organization whose objective is contrary to the Bible, and, hence, is under judgment by Jehovah God. (Compare Revelation 19:17-21; Isaiah 2:4.)
Since Watchtower joined the UN they've condemned themselves out of their own mouths.
Watchtower effectively dissociated itself - and In this instance, then, I fully agree with the shunning they deserve!