Hello William,
I was looking over our documentation and I found some info regarding Zendesk.ParticipantId as an attribute. I was able to track down the original thread from your screen shot and I can see that George Ganahl said the following:
the Zendesk API does not currently allow for anything except using the Agent as the requester when no matching entry is found in Zendesk.
I'm not sure if there have been any changes with the Zendesk API, but I did see that someone has recently submitted an Idea to the Genesys Cloud Product Ideas Lab that is tagged as Future Consideration that may be related to your request:
https://genesyscloud.ideas.aha.io/ideas/OPCRM-I-33
If you click the VOTE button on that page, it should notify you via email as this Idea progresses through development.
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Jason Kleitz
Genesys - Employees
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