Hi Maggie -
Unless something has changed recently with Appointments, I don't believe you can delete an Appointments Event from the list regardless of whether it has been launched or not.
A recommendation would be to update the Appointments Name to include a ZZ or XX in front of the Event Title to push it to the bottom of the list. Example: ZZ - ABC Event - Do not use
Hope that helps!
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Rebecca Yousif
Senior Administrator, Event Technology
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