I think he could have been thrown over the fence (they've done that before with birds they've killed). Two days ago, they had one of MY roos locked in their coop/pen. He's the baby of a cornish x so he couldn't have flown over there.
He was stiff, completely stiff, but under his feathers he was still somewhere between 65-75°, not stark cold. He was definitely warmer than the 50° it was outside.
Another odd happening was those kids were looking around my yard where he was, last night, while harassing my other roo with a remote control helicopter.
I just find it very odd that a hawk could swoop in and none of the other 11 roosters made a sound (and the hawk completely disregarded the birds he could catch and eat).