WP_DEBUG_LOG was not set to true. Added that into the wp-config.php and then I could see the stack trace of what it was that happened. There was an error in file.php that was looking for something that is part of a Flywheel modification of some sort. Did a re-install of WP core and then everything worked right! Thanks for the hints that I needed to get this going!
Be aware that moving FROM Flywheel that there are several places that I had to remove things to get things working right.