Fixing VirtualBox Only Showing 32bit Windows OS Options
Original help was identified from this article Why is VirtualBox only showing 32 bit guest versions on my 64 bit host OS?
In browsing through the comments, I saw mention that the root issue is that Hypervisor running interferes with Virtualboxes virtual management, so I disabled Hypervisor service, repaired the install, and rebooted. I also disabled automatic start for Hypervisor. This resolved the issue without requiring the uninstallation of the Hypervisor feature in Windows.