There are more players. I remember Prijovic playing for Serbia at the 2018 WC while being a PAOK-player.
Glykos was subbed in at the 2014 WC when the first keeper (don't know his name) was injured. He was at PAOK at that time.
Swiderski played in the 2022 WC just after he left us for the States.
Your friend Christodoulopoulos was for sure.
I have to dig in my brain. And maybe the internet. There must be more players. I remember the squad lists in "Voetbal International" mentioning PAOK as the current club. Not only in the Greek National team.