I used a Page Properties macro which has the columns for QA Reviewer and RA Reviewer. When a user assigns a reviewer in the Page Properties macro, it automatically assigns that user to that approval. However, if I chose to reassign a reviewer to someone else in the workflow, it doesn't allow the new reviewer to approve.
Here is a snippet of my code...
{state:Review|approved=Final Approval|rejected=Draft|updated=Draft}
{approval:QA Review|assignable=true|hadapproval=Document Control Review|user=@QA Reviewer@|group=comala-qa}
{approval:RA Review|assignable=true|hadapproval=Document Control Review|user=@RA Reviewer@|group=comala-ra}
{state}
