UPDATE: I seem to have fixed the problem. The analytics account ID located under 'Analytics Settings > Edit Account and Data Sharing Settings' in my Google account dashboard did not have the extra '-1' on the end.
In other words, pull the correct account ID from the code that Google generates for you on this page: 'Analytics Settings > Profile Settings > Tracking Code' instead of this page: 'Analytics Settings > Edit Account and Data Sharing Settings'
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