someone of our team managing the events in civiCRM yesterday realized that there are events missing from the the 'manage events' page in our wordpress installation (4.7.31)
in researching i found this Events 'missing' after upgrade to 4.7.19 which very much looked like the issue, but the quick fix of updating CRM/Event/BAO/event.php didn't change anything so i just updated to 5.2.0 as i assumed this should fix it.
unfortunately the events in question are still not shown.
Checking contacts who had been participants in one of these events does show the event listed there and i can get a list of all participants - but i can't manage/edit/duplicate such event.
any hints on how to debug/resolve this?