Might as well ask DTG to switch it up and use the forthcoming UE6 or even 7. By that time Epic will likely have added 'scratch and sniff' tech. Good for the dining and buffet cars (if Matt P ever gives us any).
They should have used the Nacon / Kylotton KT Engine. Then DTG would have a great excuse for the jerky and stuttering train movements.
Interesting that the OP uses the word Massive. Massive Entertainment (owned by Ubisoft) develop the SnowDrop engine which, if recent releases are a worthy measuring stick, is an outstanding basis for terrain-heavy games. I am currently playing through Avatar on PC and the terrain and foliage are just sublime.
