The rope shortcut requires level 40 agility (Disease got me down to 38 and I couldn't use it till I recovered.) Sanfrew serum works better than Relicym's because its easy to get poisoned as well as diseased down there. I had the same problem with the High Priest - don't use a poisoned weapon.
I got bored killing goblins in Lumbu and went exploring. Found this old house and in the baesement a casket. Once I opened it couldn't leave the room and got killed quick.