There's a great big whopping difference between when your consultant says "change what's written on that board in the background" and "change the whole plot of the episode, that's not how the world works".

I'm sure he told them, I'm sure they know; but the whole plot turned on it.

Sometimes when you realize that superman flying around in space is impossible from a thermodynamic perspective no matter how "super" he is, you just gotta shrug and say "dude, he's superman".