Criminal charges are incredibly unlikely. This was a freak accident, in which they took plenty of safety precautions, but somehow managed to have an accident anyhow. They didn't actually hurt anybody. There are no real criminal charges that could be brought against them.

And it will only be lawsuit city of Discovery Channel doesn't offer an appropriate settlement. I'm sure that Discovery Channel has plenty good insurance, and plenty of cash on hand, and will over to cover the costs of the damages to those involved, plus a little extra to keep them happy. There will only be lawsuits if they don't offer a reasonable settlement, which I would find unlikely.