Adrian did not see wrong when he saw that the ronin sliced off the head of the Crimson Asura Gorilla in one swing of his sword. The sword style made him remember the style of swordplay that the ranked one warrior player named Blade used.
Although Vayu also uses a swift sword style, the one that Blade uses is more on the quick and lethal. Vayu uses a sword style that is quick yet elegant when seen as if he is dancing with the blade. The two different sword styles might be attributed to the teacher that Blade got when he entered the game despite Vayu being his real-world sword instructor.
Adrian did not question the ronin as he does not seem to question his abilities. He did feel that there are a pair of eyes looking at him when they resumed travel. The ronin must have seen the unique way that Adrian is using talismans unlike the Charm Masters.