Just to clarify, I've not seen anything that says there are 10 Golems exactly. I may well be mistaken but I rather suspect 10 is just a tidy made-up number based on our tendency as humans to count fingers.
While the res needed for Elder Golems is certainly high it would be very nice to know for certain if Golems beyond #1 are 'just for fun if one wishes' or if they do in fact count toward the server goal. Seems like that will make a huge difference in how the event is played and very likely in how players deal with other over the course of it.
If all Golems do count (and Golem level makes no difference) perhaps it would be wisest if we all focused on clearing as many lower level Golems as possible before worrying too awfully much about the Elder sort. No doubt there will be plenty of time to face their challenge as well.
Just for general info "for now" on the Test if a Golem is defeated before the specific quests to attack and destroy him are active he will not come back. It doesn't matter if the Island's owner bashes too quickly or if a well-meaning friend clears him away, without the right quest running there comes no second Golem. Here's hoping this is sorted speedily.
The Golem quest chain can break