Ok. I’ve gotten rid of the error message (there was one $vbs_post_ey that I’d forgotten to change).
BUT, now I’m getting the slug writing correctly, but it’s not including the post type in order to reference the correct single post template. In other words, for an ‘en’ submission it’s giving a path like this: http://www.website.com/stripped-slug instead of http://www.website.com/en/stripped-slug
That said, it now works fine for the ‘ey’ post type. Not sure why it works for one but not the other…