In order to ensure your formulas use accurate, up-to-date data, de do not recommend using trigger.body.message.raw
inside formula steps to retrieve object information. Rather, as a best practice, we recommend using the object ID from the event and fetching the record from the vendor. There are several reasons for doing this: first, you ensure you are working with the most current version of the object, and second when fetching the record, that call can be made through a VDR.