Workspaces in Gnome 3 are dynamic, there aren't just two or three or four, there is always one more than you have open. In MGSE your best bet for a way to create a fixed number of workspaces in a grid is to find an extension doing that (if it exists) on the extensions.org site.
Thank you for this thread. That’s all I can say. You most definitely have made this forum into something special. You clearly know what you are doing, you’ve covered so many bases. Thanks!