I think that is the reason.
Are emails going to all the people, including the right recipient, or just the wrong one?
Is this WF sending emails to a DL, or a computed recipient?
It seems to me you have a DL for system owners and all get the email no matter what? In that case you need to streamline the WF to account for the system owner of your case.
Nosh Mernacaj, Identity Management Specialist