Im going to explain this as though im grabing flag you may find other ways of getin people down there but heres my way.
1.Take alliance flag and run out and head towards there graveyard
2.Go all the way near there instance they leave through and you will see a tree to the left of it.
3.Head towards behind the tree dont hop down till you see kinda a pit behind the tree.
4.Hop down there and wait for them to kill you (make sure they saw you hop there) now sit there and die.
5.Now they will hop down to grab flag all that hoped down there are stuck there untill they exit the wsg.
(this may also work on stupid people that folow you and you mind control them or they slip)
I dont know if this was posted all ready if so my bad remove it.