These "mistakes," if they are mistakes as you suggest, are a direct result of Jack Smith appealing Judge Cannon's ruling in favor of a Special Master to first review the documents to separate out the classified documents.
Smith appealed the ruling because he wanted to speed up the case and felt the Special Master would slow things down too much for his schedule. Cannon ruled that Smith must stop reviewing the documents until after the Special Master first reviewed the documents. Smith appealed and had Cannon's order overturned.
And this was the eventual result.
-PJ
So Cannon wanted to make sure that the evidence was handled properly and ordered a Special Master to review the documents. Smith got her order overturned and promptly screwed up the evidence so badly that none of it should be admissible.
Is that about right?