Symptoms

When trying to deploy using PandD an error gets thrown Process is referencing "Missing ID" unknown that could not be found Process - An item with the same key has already been added
 

Diagnoses

When expanding the PandD error it showed that the issue was on SF integration step on the workflow. When we reran the integration wizard and redeployed the process we ran into The "item with the same key exists" error. If you just open up the process and deploy, it deploys correctly but then PandampD errors. So the issue was with the SF integration step itself.
 

Resolution

The issue here was that the folio being passing in twice, once from form level, and once from Process level (SF integration) and  this will cause the error. Removing unwanted mapping value resolved the issue.