First of all you need to some how camp the area where you killed one... If that was kind on their side of the filed you have you move up front and pop totems.. untill you have that area, drop some searing totems out behind the pillers might help.

Also, It depends on how many that are left on their team.. if you basicly killed lerts see 3 but they have 2 healers left that forever piller kite.. then it is your healers responsibility to atleast follow 1 of them at all time.. also.. if they dont have any ressers left.. I have some times left my 3 shamys spred out in a way so they basicly cover all sides of close pillers. and then hunted them solo with my main and the other healer. That can work as well.. but make sure its only healers left.

In situations like when you have killed most of their team but they have 1 or 2 healers runing around.. i normaly go /wolf /spredout /dance alittle and they tend to leave. As your show them that you got it under control.. Taht way you also will regain your NS which will help you when they piller run. Just make sure you mount and run on them, drop a earthbind, shoch with frost, and Burst them with NS down. Mostaly they are gone then. as the only thing they will do is to run away somehow. with no sup healing.

Ressing teams was a problem for me at a point.. its never anymore.. you and your healer just have to get practice with it. And prioritice which healer you will focuse on later.Ignore the resto drood. but kill their prist..etc