YOU SAID:
You have no idea who he is, do you?
INTO JAPANESE
彼が誰なのかわからないですよね?
BACK INTO ENGLISH
You don't know who he is, right?
INTO JAPANESE
彼が誰なのか分かりませんよね?
BACK INTO ENGLISH
You don't know who he is, right?
That didn't even make that much sense in English.