Brazil's mysterious tunnels made by giant sloths

It's sad to think we missed witnessing those awesome critters by a few millennia, probably because they were wiped out by our stone age ancestors. I wonder if there is some hope of bringing them back in the future, similar to what it proposed to mammoths. Or are the DNA samples in found reminds too degraded to be recoverable?

Strange that they consider the claw marks on the walls to be what created the tunnels. At first glance looks like a lava tube or standard cave opening that was expanded by the animals -- perhaps trapped within and "farmed" by humans or Neanderthals?