This is an odd one. I've been chasing my tail searching through the database trying to figure out what's going on here, and finally tried deactivating this plugin. Suddenly, the page is editable.
The page is visible on the front end and visible from the back-end page menu, however when I click to edit the page, I get a blank white screen.
I've tried deleting and reinstalling the plugin, clearing the cache and generating a new sitemap. No matter what I do, if the plugin is active, the page is uneditable.