RTF is a global modification that replaces all towns in the game.

They don't really seem like heroes...

In theory, Duncan could have survived:D

Added 2 minutes later
And it's not very practical to take heroes from the same city.

Magister Jensen will definitely be a hero, and the rest can be discarded, and of course, there will be heroes from other cities, maybe even some kind of beastman from Kartal, and also disgraced heroes from the empire

Added 1 minute later
I was also thinking of bringing Duncan back; he could have been stunned, or brought back to life by some priest wandering the streets of the city.