Based on what I see here: https://www.fullcontact.com/blog/asynchronous-delivery-with-webhooks-and-testing-locally/ it seems that Marketo is just acting as the API Consumer in the diagram. As Sanford Whiteman mentioned you could call the service again and get the 200 response with the enriched data, but you might be charged for 2 credits, one for the 202, and one for the 200. For a task like this you could spin up a few AWS lambdas to make the necessary GET/POST requests, and one lambda could be attached to an API gateway that handles the POST callback behavior. Does this enrichment need to happen in real-time as leads route, or is it a batch process where you use your monthly credits at once?
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