thanks for all your help guys!
turns out i was just unlucky with spawns, 7 attacking the 3rd chosen my first 5 tries.
so i convinced a guildie (monk) to come out of retirement specially to help me. So we did the mission and neither chosen 3 or 4 were under attack -__-
"but..but it was hard when i did it earlier"
he just loled at me and went back into retirement