It is currently impossible to see any details relating to workflow webhook trigger failures. When you hit the webhook endpoint, you receive back the id of the webhook, regardless of whether the workflow even ran. The specific use case I’m trying to deal with is adding and creating objects in hubspot from a 3rd party system. When you hit the endpoint with an object record to identify which object you wish to update, there is no indication whether that record exists or not. So if the object doesn’t exist, the workflow won’t run, but there is absolutely no way to know that it didn’t.
I suggest that some form of notification be added to workflows with webhook triggers that allow for feedback in the instance that a webhook was received by then didn’t enrol in the workflow, because the ID didn’t exist. Even better would be some sort of trigger action that allowed this to be handled within the workflow itself, so that if the ID wasn’t recognised, a customisable action or notification could be run.