Responses are confusing, so I have to assume there's more to the OP than what's posted in it.
That said: How is being L80 an excuse to KS someone? Or this the term KS being used differently here?
The thing is there's no 100% rule what and when is a ks ...
So some say who seen him first , some say who got aggro , some say after 10% killed ,some say who camped him,bosses isnt ks just competition,some FFA all and it goes on and on
Most will be bending the rules to fit there situation thats why alot think diffrent when it comes to what means kill steal
Now to op never give up keep on trying you will get the discs
You will faster get the discs if you just buy them
Instead of camping him for weeks just grind up some gold
Sure you can camp him and hope to get group invite that most likely get left out
All come down to what king of player are you ,hardcore ,ok,noob,super noob(dont trip about my stages just random)