I tried putting the code received in my Marathon ingame inbox into the link from the QR code — at first it gave me a 'code invalid' error so I tried it a second time. After that it sent me to a page where it said my 'survey was completed or my session timed out'. I have NOT filled out the survey, but I want to. If the team needs my code in order to access data for it I'm happy to share in private.