As long as it's in off-topic then you should be able to post whatever you like, I'm afraid the people who are selling these codes are most likely either selling you crappy ones or pirated ones that you could get for free anyway, I recommend going to piratebay or something and grabbing a copy off there for free so you know whether it is indeed the game that's at fault but since you didn't purchase it directly from the origin store you won't be able to get your money back or get the problem fixed anyway. Thanks to DRM the pre-owned games market is pretty much dead, I'm sure there will be those who will angrily disagree with me but all these people selling codes and such are likely either selling cracked software or codes that could be just legit bought from the developers for roughly the same price anyway.
I'll just say it again for the emphasis, don't buy these game codes, DRM has practically rendered them buggy and unusable for legitimate gaming, the people selling this stuff are most likely doing it to earn some quick Bitcoin, the only DRM I know that's got a working trading system is steam but even then that's going to be dodgy and unreliable like anything developers make that actually benefits gamers and not them.
That's not how it works. Origin is a centralized system owned by EA, you can't provide it "fake" codes. You can enter real codes, but they may be taken which wouldn't even allow you to download the game let alone start it.
