Out of the recesses of my mind I recalled virtual TTYs (console prompt) are a thing: alt+F2 gets a local TTY from the osmc boot/welcome screen, which is exactly what I need to figure out what’s been going on.
I’ll reference this in a reply to Accessing the command line - #8 by ActionA - perhaps the “accessing the command line” wiki can updated to include 
Thanks again Jim, appreciate your help