Going dark is not having any contact at all, i.e., it's like he has died or has gone to the other side of the moon. It means never calling, texting, emailing him or responding to his communications. It is also called the final resort on some forums.
NC is going dim and only having contact w/him in case of an emergency or issues dealing w/your daughters or legal issues.
TJP, he'll contact his daughters again very soon. He knows that they were upset w/him, so he's going to remain quiet until he thinks that they have "forgotten" about the issue that made them upset. You are absolutely correct, your daughters are old enough to forge a relationship w/their father, but right now, it's going to be tough to do when they are acting more mature than he is.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
