Output Parameter Determination - Generate email output to AP exclusively else RE

Hello Community,

We aim to set up OPD to send email to a contact person when a customer has a contact relationship, else send email to customer bill-to. Currently it generates an email output to both contact and bill-to when both exists.

Our current setup for determination step receiver and channel:

If we try to set AP as exclusive, it doesn't generate any output for customers (RE) without contact relationship.

And for Channel the exclusive indicator doesn't trigger as desired, it still generates email both to AP and RE.

We thought of changing the results for the determination step: Channel and add Role as a result instead of a condition, but wasn't able to maintain the role as a result.

Do you have any advice on OPD and how to handle these types of scenarios?