I decided to move up to Delphi 11 and just use their default platform installer for Android. I also decided to retire the old Android ZTE phone. I'm able to compile, debug, and run both Android and iOS apps from Delphi 11 now.
I was still getting the weird error listed in my previous post for the DelphiVersions project though, even after deleting all temporary files and recompiling. Finally, I just renamed the project to DelphiVersionsMobileBroken, created a new blank mobile app, added the forms, removed the default form, set up the icons and version info--and it works!
Something was seriously amiss--but everything is back working now--and in Delphi 11. Whew!