Ghost of the Railroad Engineer:
Thank you. Please help my poor fellow ghosts to rest in peace, even if only for a while...
Some might share their dream fragments with you as they expire, which may be informative.
If you give them peace, I will find some things among the keepsakes my friends left me that may be helpful to your quest and give them to you...
Oh, but watch out for Nellis. He and his followers have gone completely mad and there is no getting through to them.