I am having this same issue, and I have a ticket open with Qualtrics support. I can see on the Salesforce side that the Outbound message is going out (and also verified with Salesforce support), but it isn't being seen by Qualtrics. I can manually trigger the same workflow rule (using a checkbox on the existing record) and it works perfectly. But when it triggers from a record creation in Salesforce, the workflow rule is firing in Salesforce, but Qualtrics isn't actioning. There are no error messages in Qualtrics. It is very frustrating. I've tried rebuilding the action, and it still isn't working.
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