Workflow Email to Owner's Manager

I'm trying to send an email to the manager of the Owner of a Custom Object record (Coaching From) when the record changes from one status to another.  When I select the "Relative User on Record" option, it gives me the Coaching Form Owner (which I am using at another stage of the process to email the Owner), but it only gives me "Account Owner's Manager" and not Coaching Form Owner's Manager.  

Since this custom object is not associated with an Account, there is no email value returned based on "Account Owner's Manager".  So, it doesn't look like I can use the "Relative User on Record" option.