How do we respond to the specious argument that 'Umar wrestled with a jinn, and that jinn are inherently unseen, and how did 'Umar know that it was a jinn?

The story mentioned has been previously cited in Fatwa (definition) No. 146035. In it, Umar dialogued with the person, and perhaps through this dialogue, he realized that it was a jinn. The absolute statement that jinn cannot be seen, based on the verse: "Indeed, he sees you, he and his tribe, from where you do not see them," is incorrect. The verse does not indicate that; rather, it indicates that he sees us from where we do not see him, and this does not necessitate the absolute negation of our ability to see him.