I have now added the new blog manually, incl. the relationship to the user (me), via the 2 mentioned DB tables. Now the blog shows up, incl. the newest post of the user
One thing that still does not update correctly is the ‘last updated/active’ info for the blogs listed. It shows the newest post but DOES NOT UPDATE the ‘last active’ tag. If no one comments here, I will report this as bug end of this week.