re shunning
there is kind of external / internal doctrine of shunning:
External: We shun murderers, thieves, ... according to the Bible principles. We do not break families, normal family relationship continues. see here: https://www.jw.org/en/jehovahs-witnesses/faq/shunning/
this is what they pretend toward the public.
Internal: see the paragraph 7 here: http://wol.jw.org/en/wol/d/r1/lp-e/2016127
This is what the org teaches in the meetings, talk, conventions.
They can always try to trick somebody and pick the right version based on audience.
And I fully agree with Carla. Either they stop shunning or it is better not to allow grandchildren to spend time with them, They will try to instill Watchtower into the children' minds.