I think your plans for Drayden should be this...
Druddigon - The best one for his lead is Slovakia, because while Egypt can hit hard, it has Revenge which could easily decimate her, while Slovakia is more defensive and can take these hits well. I can't recall if she'll be slower than Druddigon but relying on STAB might help her here.
Flygon - I know that thing has Earth Power, so Pakistan and Slovakia are out, and Crunch will batter Eurasia hard, so I think it may come down to Australia throwing around STAB neutral-damage Surf here. Kinda surprised it has no Dragon moves though.
Altaria - It has Cotton Guard but Eurasia can use Power Gem to get around that, so an easy one here. Fire Blast also won't be much even without Thick Fat but that's because Eurasia can take special attacks really well. So, an easy win for Eurasia here.
Haxorus - This isn't 6th Gen so Pakistan still resists Shadow Claw, and even with Dragon Dance boosts Haxorus can't easily put a dent in Pakistan thanks to its high defense and tons of resistances. But I know you already planned that one.