---- EDIT (2018-09-26) ----
As of the recent patch (1.8.0), this is now obtainable.
See the link here:https://forum.paradoxplaza.com/forum/index.php?threads%2Fcon...
---- Original ----
Just an FYI on this.
As of writing this (September 2nd, 2018) the Trains! scenario will fail.
Seems like it will fail due to spending 20 weeks with < 1,000 pop.
No matter what you do, it will fail.
Post about it on the Forums.https://forum.paradoxplaza.com/forum/index.php?threads/ps4-i...
*It's a bug and will be fixed next patch.