I came home to find these guys cruising around my yard yesterday. Three live and one dead, last time there was 14 eggs (non hatched) so I'm guessing there's more to come.
Yes the parents roam around freely in the yard. They are way to big to escape, unless I leave the gate open. Yes they do dig big, long holes that aren't very deep and run parallel to the ground. For instance the hole mine dug is 8 feet long and over three feet wide on the inside. Here's a pic of the entrance and one looking inside.
Here's some more pics of the dad and one of the babies. My foot is in there for scale. Also if you look closely you can see the female in the back of the hole.
I couldn't take it and dug up the nest, I figured it's been three days and one was found 100 feet from the nest. I found one more alive and over 20 eggs. About half the eggs were cracked and looked like chicken eggs on the inside. I buried the others that looked intact. Here's a pic of the eggs, the one we found and all four eating