I found this section of the article the most interesting
Is Zorn talking about a legal requirement that the prosecution propose a near certain guilty scenario?
I don't think there is any such requirement.
In this connection, I've been thinking about the California case Vincent Bugliosi discussed in his book
Till Death Us Do Part. He couldn't prove the defendant shot his wife, and he couldn't prove the defendant hired someone else to shoot his wife. But he convinced the jury he must have done one or the other, and got his murder conviction.
The prosecution's problem in this case is similar, in my opinion. Lucky for GZ, none of them are Vincent Bugliosi.