If I take the train to North Underrail with Gunslinger, the following ending slides are shown in a row:
"And now you both board the same train to North Underrail. Perhaps your cooperation will indeed continue beyond The Compound."
"However, your cooperation lasted only up until your goals at The Compound had been achieved. After spending some more time in a much calmer environment, you both went on your separate ways."
Looks like the second slide shouldn't be shown.