If the predator was armed (they might not have armed because if it was just being used for surveillance, it would be able to stay in the air longer without a couple heavy hellfire missiles on board). IF the predator was armed, I am not positive they can be guided by laser from the ground, but that is irrelevant because predators have infra red cameras. The laser sighting from Tyrone Woods would have at least given the operator of the drone the co-ordinates of the mortar team and he could have taken them out with the click of a mouse.
Thanks. The mortar fire is what killed them.