Sorry for any confusion in this string of posts, but I eventually found that Closing Tasks to Updates didn’t work for me because I was doing it in our EPM Dev environment and later discovered that we have issues with our EPM Dev environment that need to be fixed.
This feature does work in our EPM Prod enviorment when I follow these steps:
All tasks are set to publish No in the plan, and then I close tasks to updates (including row 0) using Server Settings > Close Tasks to Update > Select the project > Lock all tasks on all pages (using the page control at the bottom of the list) > Publish.
