@RokuDanny-R... quick update to let you know that this seems to have **partially** resolved itself. When logging in as a guest for the first time, I still see a large set of default guest apps/icons (the original normal behavior), but then they disappear from the Home screen after a few seconds, and the screen refreshes to include only 4 default apps. However, I am now able to install my own guest apps and have them display on the Home screen. [Or perhaps this was the behavior all along and I somehow missed it?]
My main concern originally was that guests would not be able to install and see their own apps. That no longer seems to be a problem. And frankly, I'm OK with most of the initial set of default guest apps deleting themselves, as it saves my guests time customizing their own set of apps and not having to delete/sort stuff they don't want.