Jetty returns 404 when calling code manager URL behind nginx proxy.

I have set up an nginx proxy infront of our puppetmaster. Now I am trying to do a request to one of the endpoints for codemanager. However, i get a 404 response from Jetty when i do this request through the proxy. When i do the same request directly to the puppetmaster from the same server i get a 200 status. Strangely enough, in the file puppetserver-access.log, it shows a 200 status for the exact request which returns 404 on the machine behind the proxy. How can Jetty report a 404 status back while writing a 200 status in the logs? My suspicion is that Jetty is somehow configured to return 404 when a certain request signature is detected. Any ideas?