I don’t think you should come and tell them Drashos and Mekoros.
When a family has a Tzara, they can’t think about reasons and Cheshbonos why it’s happened. They only think about their loss.
Best Nechama is to cry with them and show them your pain.
Later on, when the wounds are not so open anymore, you can help them think about all these things.
That’s just my humble opinion.