when you say that "Our digger is working backwards",
you mean Whale Digger is entering the btc privatekeys backwards through clam block time?
Yes.
Why isn't the digging random? Why would there be a predictable digging of clams going backwards?
Why doesn't it jump back and forth all over?
We can only guess at his reasons. I don't see what advantage it gives him to disclose his holdings in this way, so maybe it's accidental.