Clever cumans

Cumans recognize me if I take cuman’s clothes or if I kill one person from their camp (the others don’t see or hear it) and take ALL but ONLY his clothes. Even if I have helmet, covering all Henry’s face. Is it a bug or I do something wrong? I saw a video where Henry can select one of 3 frases to tell to cuman is it a free play or a mission?

the 3 phrases is a mission i think, as far as wearing cuman gear, it’s never worked for me outside that mission.

The disguise only work in a specific quest, to infiltrate the bandits in pribislavitz or whatever it is spelled.