Hello Stefan, I have a branch of Krajnak in my family tree. I know this is spelled a bit differently from your Krajnik but could it be the same family? Juraj Krajnak married my grandfather's sister Maria Zaleta from the village of Olejnikov.Maria's family was Hrabcak. I understand that they later lived in Martin, Slovakia. Together they had 10 children.
Could we find a connection? Thank you for your help. Diane Hassan