Why "Terminate Employment" process does not populate Termination Date

Summary:

We have several employees with multiple assignments. We are using the new redwood "Terminate Employment" process to terminate only specific assignments. However, it looks like it's only ending the assignment but not really terminating the assignment and Termination Date for this specific assignment is not populated as well. What would the appropriate process to populate the termination date only on the specific assignment and leave the other assignment active?

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