The pool report ... said "The second offense was when No. 22 from Iowa picked up the ball and failed to immediately pass the ball to the official after the whistle was blown."
I've been around interscholastic basketball (not intercollegiate basketball) for fifty-five years, as a player, coach, and official, and have never seen this called.
As an official I've warned players about this kind of activity on many occasions, even stopping the game to have a serious chat with the player, but I've never called it, or observed it called.
It takes a lot of courage by an official to call this on one of the top players in the nation, putting her in foul trouble, in a national championship game watched by millions of people.
The calling official must have had a good reason to call it?
If this happened in my biggest middle school game of the year, with one of my best middle school players, I would have definitely passed, or just warned.
But granted, I know more about rocket science than I know about NCAA rules.