Heart of Nightmare [Bonus Mission]

I installed the map using that tricky method, the link to which is in the first post. I placed it inside the licensed game folder. It displays and works perfectly, BUT - instead of Svetlana, I get the hero Vyacheslav... and it's hilarious and frustrating at the same time when trying to complete the mission for the Necropolis faction with a hero who doesn't have any dark magic skills at all. This annoying thing rebuilds the Fortress of Sanctuary into a Fortress of Light instead of the required Necropolis, and so on. What should I do? Is there a way to fix this?