As I understand, and if that letter is true, One of those men is the man seen in the Wikileaks footage. He is the one carrying a child from the van.And he was there.

Now it has been along time since my military training (infantry) But as I remember shooting at the wounded or at aid workers was considered wrong.
Perhaps things have changed. Perhaps honor is no longer a part of training. It has been a long time.

Now to your point of "bringing children to a battle". They didn't.
The battle was brought to their neighborhood, to their home. They were passing by and stopped to render aid.
And again, targeting unarmed aid workers is,,,,,highly questionable.

To me I see little difference between this and the incident at Waco. Just a different neighborhood.