Hello, sorry to hear about your problem. This is a real strange case that you are having. As fate would have it my graphics card burnt out so I too just bought a R9 270x and got the 2 free game code as well. I bought mine from Newegg so if you bought from somewhere else maybe it is an issue on their side. Newegg emailed me my code, I went to AMD's site created an account used my code and picked my 2 games. Never did they ask me for proof of purchase. To be honest with you I went to http://sites.amd.com/us/promo/never-settle/Pages/nsreloadedforever.aspx
to enter my code...all the games are on the page. I am not familiar with the link you posted since the site I posted is their promo page. Let me know how things work out for you.