No one can give a really convincing reason about his age being a problem.
If immature it is show me something I can consider to make me think that way with you towards him.
Well, what can really be considered is his lack of experience of being an admin and using the right commands carefully with no mistakes.
Since he plays cs for quite a while now, not since really long and he learned that well about it and spends a good time in the server. I think that he deserves a chance!
He was a noob just 3 months ago, this means that he is a fast learner and he can be a perfect admin with the help of his brother (and others of course) he can be a perfect addition also because at this current age he's mostly free to play.
I support this admin application. 144p 
PS: I also live in KSA atm how the heck do you manage to surf with 160 ping? GAH.