IIS reverse proxy "Launch Designer" relative path issue

I’m configuring IIS as a reverse proxy to handle SSL requests. I’m using URL rewrite and ARR to route them to port 8088. Everything is configured, and working great, except it appears the “Launch Designer” button in the header of the main site is not created using a relative path. All of the other links work great, and display the forwarded domain, but that link is trying to reference the forwarded address, which is localhost:8088/main/system/launch/designer/designer.jnlp.
Is there anyway to modify that link to use the relative path so the correct domain is displayed, and the link will work as expected?