Issues with setting up persistence for a JDA application

We are having issues with the JDA application VIPs that some of our vendors use and it seems to be specific to vendors whose source IP changes. Right now the VIP is using source affinity persistence, but JDA is recommending that we use cookie persistence, cookie rewrite specifically. I set this up in our certification environment first and it worked as expected. We implemented the same persistence profile on the production VIP and it did not work. They said they start seeing issues with the Session ID changing. I verified that the VIP and persistence profile were identical to the certification setup. We tried this both internally and externally on the production VIP and had the same result. Has anyone worked with JDA and can offer any advice?