Okay, here's what happened.
Bill O'Reilley (I'll refer to him as BOR if that's allright

)made a false statement. I think this was unintentional, seeing how he is generally right-wing from what I've seen of him (though not
perfectly right wing, he seems more populist sometimes). He has a show every day, and has to think of responses lightning fast, so it's easy to imagine a scenario where he had a bit of dyslexia. He read something a good while back, but got the two parties involved mixed up.
So far, we're probably dealing with an unintentional mixup. The commentator in the clip is blowing a lot of hot air by calling BOR's comments slanderous, which implies intent. Mr. O'Reilley may not be a historian, and he may be mixed up, but to say that he intentionally lied is doubtful.
The problem isn't O'Reilley's misstatement of truth. The problem is Fox altering the transcript, and then BOR wouldn't admit error and issue a retraction. He should have simply said, "Whoops, I got the two groups mixed up. It was the SS that murdered the americans, not visa-versa. However, the historical record will support my broader argument which is that americans were not always the heroic angels they are portrayed as in WWII." That would have been the reasonable thing to say.