"Thank god we will all be gone because If Monty ever found this place, we would have been in a world of shit."
"Maybe now with us all gone, the children will truly be safe"
This seems to be the good ending:
Monty loses, the children are safe, and you're not in a world of shit.
Dempsey actually wants to die there, he knows what would happen if Monty found the place, and it doesn't seem to be any good.
Meanwhile you have the other cipher:
"If you are, then all hope is lost. I'm the last one. The others... they're... gone. We failed."
"No matter what we do, what we fix, we still end up here."
Clearly here you see Dempsey saying the situation is bad.
But Dempsey actually has a last hope. And that hope is Richtofen:
I hope Richtofen established contact with the others. Woke them up. It's the only way now. It's up to them.
Now this rises questions on their own. In particular, it means that some version of Richtofen survives.
As I've said, the answers as I see them are in The Giant.
I would say that the paradox isn't resolved at that point of time, but don't concern yourself with that just yet.
See if you can understand the rest of The Giant first.