Stanley Kubrick was busy with his own projects at the time he was supposed to have been filming the fake moon landing, and, perfectionist that he was, he would not have interrupted them. Furthermore, he would’ve insisted on filming on-location.
As for the Van Allen Belt, they got through it very carefully. Getting through them without being fried isn’t impossible, just difficult. Curious Droid will elucidate.
And if it is indeed impossible to encroach on God’s domain, why bother forbidding it? It’s like having a law against dividing by zero! If they can’t do it, you don’t punish them for trying, you just sit back and watch them fail!