Moving MS Office 2011 from Mojave computer to older High Sierria machine
So moving the apps out of and back into the Microsoft Office 11 folder seems to have helped. After doing it, I got prompted to register the software over the phone (the product key no longer worked) using a lengthy number.

But I'm still seeing some weirdness with a There is a problem with the Office database error when I open an app and Outlook won't open at all. But I am closer, at least.