Symptoms
View's 'Create' method off of a SmartObject item reference to a SQL Service SmartObject creates database entries but fails to return the created row's ID.
Diagnoses
The issue was with the View method 'Create'. There was some sort of disconnect between SQL, the SmartObject, and the SmartObject reference on the View when returning the created row's ID.
Resolution
Used the 'Execute a SmartObject method' action to directly call the SQL SmartObject's 'Create' method and the ID was returned successfully.