Which correctly distinguishes wuḥdān from majhūl al-ḥāl?

Narrator Anonymity: Wuḥdān, Mubham, Majhūl al-ʿAyn and Mastūr

• In both cases the person is always unnamed
• Wuḥdān always requires at least two pupils
• Wuḥdān concerns one known pupil; majhūl al-ḥāl concerns at least two with no established authentication
• Majhūl al-ḥāl always fabricated hadith