I would say WT nonsense has instigated this. I think they are having a crisis of conscience. Atm in the WT and meetings we have been told to avoid bad associations all the more. Maybe another relative of your has been df'd you don't know about, or they have stopped going.
In recent times at meetings or in the littertrash, nothing has been mentioned to reconnect with df'd relatives. This is a good thing for you. Keep us posted as to the motives. I hope they get in touch again soon-Kate xx