Their lowest resistances are slashing, crushing, piercing and ethereal. I used ethereal arrows - and vanished via door, if I was too low in health - came back then.
Which ones are your prob? The rangers or the melee ones?
I took out aggressive mode for my DK, so he and my char kept standing at the door => my rescue. So, they came to me and I took them out with arrows and my DK used his Death Claw sword. He was lvl 5 in 2-hand slashing - she lvl 5 in bow. But I used "pause" a lot to feed them with potions.
