Illusion of victory.

Next. If a Hero is inside a town, their scripted name disappears from the map database (apparently), so it is impossible to interact with them at that moment. However, I'm not sure if this is the exact reason. After all, the task that checks "Is Nimue alive" does not cause an error, which means the game can find the hero. But it cannot give him troops. The solution here is simple - don't hide the hero inside the town, but leave him at the entrance - you will still be able to transfer the purchased troops to him.