"The Challenge of Wulfstan" - "Brothers" [Campaign 2, Mission 4]

All the missions are easy – I’m playing as a “Warrior,” but, just like in Heroes 5, there are no difficulties, and you don’t need to come up with any special strategy, which is a shame.
When buying cards from the cartographer in the upper left corner of the map, on the land of demons, there is an old, damaged German airplane, and inside it, there is a “refugee camp,” but it’s impossible to get there – it’s probably a joke from the creators of the expansion, or maybe they wanted to convey something to us?...