I seriously doubt the 'hunted to death' theory. What really piques my interest is the frozen mastadons found in Siberia that have fresh flowers in their teeth, and unprocessed vegetation in their gastric system. It's like they just up and died, and froze, in minutes.
Up here in Alaska, and I speculate also in Siberia, you can have a thin layer of melted earth in the spring, and flowers blooming in just a week or so of sunshine. But underneath you have permafrost.
However there are sink holes with water running underneath, and iced over lakes/rivers that look walk-able. Walk out, fall in, and freeze next to or under the permafrost.
Firestone said they think the formation created superheated hurricanal winds in the atmosphere that rolled across North America at 400 kilometers per hour (about 249 mph).
Which could explain the flash frozen scenario.