You're blowing it way out of proportion. Punk jobbed for like 15 PPV matches and was able to bounce back within one month. Orton's credibility can never be hurt. He's at that level now. And how do you know he'll never be WWE Champion again? Have you seen into the future?
And I really don't care about all this credibility crap, JUST GIMME THE DAMN MATCH, DAMMIT!
Despite being stuck somewhere in the midcard right now, Orton is still one of the most credible wrestlers on the roster, still extremely over with the crowd. If he gets booked strong untill SumerSlam for example I'm sure a Brock/Orton match would do very good business, I also think it would be a great match.