Finally managed to solo the entire partisan on my 88 monk, the shocktroopers were indeed giving me the most trouble.
After over half an hour of camping on the east safespot trying to single the troppers I have only managed to get one, so I changed my tactic for a bit.
I went over to the west side instead, from twoma's comment above there is a small ledge up the side of the wall and made my camp there.
With maxed Hastened Imitate Death bring the cooldown to 2min, I then lull the giant on the right (since they are unmezzable) shoot at one of the troopers and move a little bit to the south side of the ledge. What happens afterward will be just luck - just ID when you see a shocktrooper managed to come up to the ledge (usually with adds) move back to the north tip of the ledge, echo them and single out the troopers (or just kill them both if you only got 2 mobs),
I was able to finish my remaining 3 troopers under 20min with this.