To be honest, there are about 1000 ways in which he could have had hoplites. Maybe there was someone else on his island that received a substantial DBP gain according to
www.grepostats.com And as for casting hoplites, you don't need a temple to receive them from a friend, but they normally leave traces of archers and slingers too when you cast Patroness. Also depends on the wall size, morale, and luck of the attack. And a 150 pt gain is common, even more is possible.
I wouldn't get caught up on this one occurance. Just build more than you had before. Plus if the dude had more swords than hops, better not attack him next time with slingers. Slingers are weakest against swords.