I have good news. The issue is fixed. Recently we extended SparkPost support to SparkPost EU. Through testing your instance I discovered that there was a bug that prevented SparkPost EU users from having their correct statistics displayed.
I did verify that batch sends do inbox. Their sends and opens have been being recorded in the background too, so this data is now restored.
I’m about to push a new release to the rest of the public. Your site files are already updated.