Those details are of no importance just as how many of them there were was of no importance. To us the message is not how many there were or who they were, its what they where(Believers) and what they’ve experienced(Allahs Mercy) thats one of the messages we take from surat Al-Kahf. Barakallahu fik wa salamualikum.

Salamu3laikum brother Ismail please do not take verses out of context the meaning is very clear, The wall has already been built during the time of Dhul-Qarnayn. It is not a present event and he helped contruct that wall to protect a civilization/group of people from joog wa majoog a destructive tribe. So please brother ask a shayk to explain to you who Dhul-qarnayn is and what was the purpose of contructing that wall. Inshallah allah will guide you to greater knowledge, salamu3laikum

” May Allah reward u with Khayr”

And goodness to you also