Correct tense: [hadn't seen him] or [haven't seen him]

I have made up the examples below.

Suppose that I met my friend, John, by chance at ABC Mall ten minutes ago. I am now talking to my cousin.

(1a) I said to my cousin, "I met John by chance at ABC Mall. I haven't seen him for at least five years."

(1b) I said to my cousin, "I met John by chance at ABC Mall. I hadn't seen him for at least five years."

Most of my non-native English speaking friends think both are correct. However, the present perfect is restricted to recent events. I have written their comments below.

"The longer you wait to talk to your cousin about your chance meeting with John, the better it is to use the pluperfect. In your scenario, the time gap between your meeting John and your talking to your cousin is only ten minutes. Such a small difference permits you to use either the present perfect or the past perfect. However, if you are talking to your cousin tonight about your chance meeting with John this morning, the wider time gap requires you to use the pluperfect."

I am not sure if my friends are correct. What is your opinion? Thank you for your time and help.