Thanks for the kind words, Mimi. I'm hardly a genius here, just persistent following the scientific method. I also posted this issue to the Apple forums, and I would have posted it to AOL forums but they do not exist.

While I appreciate all who try to help, there were those that suggested (in and out of these forums) boilerplate answers..."boot up in Safe Mode"..."create a different profile"...but they didn't actually read what specifically was happening, nor understanding that this happened on two totally different computers, running different operating systems, and completely different versions of software. If you have an identical problem in a situation like that I'm here to tell you Safe Mode and Profiles are NOT your answer.

The key to solving this issue was in seeing the little indicators as to what was happening on the lower right of the Outlook screen.

I don't know why nested Inbox folders suddenly became an issue on Outlook for desktop (remember it all worked on Webmail and on iOS) but they did and once it was gone so was my sync issue.