You are a Tattoo Parlor and you have 6 artists working for the business.  They each have separate Google Calendars and you want to include their name in the reminder message.

The best way to achieve this is to create a script for each artist (Settings > Reminder Scripts > Add).  Then name the script based on the person's name and edit the script to include the artist name. Save.
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Once done if you have already added the calendars to Appointment Reminder go to Settings > Edit Calendars > Edit find  "Default Script" and change to the script that matches.

If you haven't loaded the calendar to Appointment Reminder yet then when you add the calendar (Settings > Add Calendar)