re: Occam's razor
That's the enduring charm of these mysteries: It's easy to come up with a quotidian explanation for some of the features of the event, but hard in many cases to come up with explanations for all of it. A blade would produce clean cuts with no sawdust, but where are the vehicle tracks or footprints?
BTW, the article describes the area as a lakebed; the owners tried to create an artificial pond but the water drained into underground limestone caverns. I'd infer that the ground's rather soft and muddy.