How can I find the system source ID/owner for payroll timecard from BI Report query

Summary:

We're attempting to update some timecard overtime rate entries using the HCM Data Load using USER KEY method, but system seems to still require SOURCE SYSTEM ID value, which we can't find.

Content (please ensure you mask any confidential information):

We're attempting to update some timecard overtime rate entries using the HCM Data Load using USER KEY method, but system seems to still require SOURCE SYSTEM ID

See https://docs.oracle.com/en/cloud/saas/human-resources/fahbo/example-of-loading-payroll-time-cards.html

But for some reason when using the "User Key" method, we end end up with the error message: "A source key must be provided for the source application"