Hi @Ezra Leventhal ,
Welcome to our forum!
Based on my test, i can create the rule as mentioned in the article you referred to in Outlook desktop client:
What's the version of your Outlook?
Are you using New Outlook for Windows? If so, i'm afraid that we cannot create the rule to reply to the calendar invitation with a template. As a workaround, we can create the below rule to redirect to the invitation to your Google Calendar.
Hope to help you! If the above is not your case, please provide more information for our better research.
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