I think they were innocent men working for a corrupt organization. The UN may have wanted Hezbollah tipped off and their personnel to act as human shields but I don't believe the men on the ground were guilty of anything beyond following orders.
Very likely. They were issued unencrypted radios and told to report what they saw. Their superiors and the UN are the ones to blame for what happened. It's unconscionable to put unarmed troops in the middle of a war zone, especially one occupied by the vile Hizbollah, which has no compunctions about using the UN for cover.