Spend Authorization FYI to Internal Requester

Summary:

We have a process flow where an internal user can request a new supplier through the self-service procurement UI. The supplier registration request that the user in initiating goes through approval and after the supplier registration approval, the internal user gets an FYI.

At the step where the supplier admin team initiate the spend authorization workflow, the supplier admin person who initiated that workflow gets the FYI. However, we also want to send an FYI to that initial supplier registration requester.

Has anyone does this before? If so, I would appreciate some insight into how to identify who to send that notification to.