First off, this map was not made by me. So, I really have less idea on why some players do experience the notorious bug in the finale where the rescue vehicle navigation is not unblocking (the train door not opening) after pouring all the needed gascans.

The odd thing is, when I tested the map upon hearing about the first report of the finale bug, I did encounter the bug too in singleplayer, but much later, when I decided to try to fix it, I did not encounter the bug at all after numerous tries on singleplayer, local listen server and on dedicated server as well as on all type of difficulty.

If anyone found a way to reproduce the bug reliably, please do let me know, I will try to fix it when I have time. As for now, it is what it is. I finished the map with no bug on my first play. The bug might be random or not. And you may want to try contacting the original author of the map for real fix.

• The finale bug could be as a result of your mods conflicting with the map.
  
• Also, whenever you are going to play this map, do make sure to disable ALL other custom maps to prevent unknown conflicts.

In order to force the rescue train to unlock, use Admin System and type below command in the chat:

For SourceMod users, you can try Finale Control[forums.alliedmods.net] plugin. Type below command in the chat:
to open the 'Finale Options' menu. And then, select 'Force Finale Rescue'.