How to enable employees to contest their performance ratings

Summary:

We want employees to be able to contest their ratings and mark if they are satisfied with the managers rating after the managers selects the 'Share and Release' button during the 'Share Performance Document' step in the performance process flow.

I understand the the Final Worker Feedback step is there in the performance process flow but if select it then the employee is only able to add free text response.

We want to be able to add a questionnaire or yes/no field as the final step in our process flow so employees can inform the administrator is they want o contest their rating.