This is also true

“The enemy can kill the hostage in seconds once they know a rescue attempt is underway,” Mulroy said. “To be successful you have to have almost perfect intelligence, incredible execution and quite frankly some luck.”

If you actually negotiate with the hostage takers you need proof of life - we're already getting that in propaganda videos

They know better than to show you more than a blanket that can be potentially owned by tens of dozens of people within a 5 mile radius

That might narrow it down but I doubt you'll see the same blanket hanging in a window somewhere - ofc it's not 100% impossible