Pete didn't make the call. I know he said he did, but that is clearly the OC. Pete, as a good leader, is falling on the sword. That's what good leaders do, just like RW said it was a bad throw by him.
He won't lose the locker room. If anything, it will enhance his standing because he is the guy publicly taking the blame. This loss hurts, but if the players know he will take the hit, they will stand by him. It's like any other business; your boss/manager/etc owns up to a team failure, your team tends to fight that much harder knowing that guy has their back.
Now Bevell, even if he was right, shouldn't have called out Lockette. Trust me, I'm pissed at the WRs, but this is where the good figure heads stand up, and wear the blame.