reports_email_activity stream does not support multivariate campaigns

[markberger]

When fetching email activity for a multivariate campaign, activity for the parent campaign will always be empty. Instead, you need to fetch the email activity for each individual child campaign found in variate_settings on the campaign object:

https://mailchimp.com/developer/reference/campaigns/#get_/campaigns

[NAjustin]

Just to be clear, this would be the effect for RSS emails and the "classic" A/B tests as well, as noted in the subreports documentation (newer A/B is really just a common case of the Multivariate type):
https://mailchimp.com/developer/reference/reports/sub-reports/

This has definitely been a deal-breaker for our use case.

(sent_to has a similar issue, which also manifests in the form of not being able to pull full history for engagement with Automation Workflows.)

[kristen-all]

Same for automations as well.