Add attendees after the event (and ensure they don’t get a welcome email)
Whilst you can click on 'View/Add attendees’ icon after the event takes place and add in the students who turned up unannounced (by ticking the Attended Event box) they will still get sent the welcome email
Hi, I have just added myself to an event in November to check this out, I did not receive an email. Have you tested this out yourself?