You also need click to move active on the slaves.

I have /assist focus in my DPS macros {I use /click macros, here}

I changed Tab to be my interact with target key on my melee slaves only {group interact is my ] key}

My tank pull macro uses Jamba to call my melee toons to me

Code:
/castsequence [target=player, mod:alt] Sacred Shield; reset=combat/target Avenger's Shield, Divine Plea, Null
/startattack
/jamba-follow master melee
Having slaves already in close range seems to reduce my chance of runaway DPS.

Don't get in the habit of spamming Interact with Target. Try to use it ONLY if your melee DPS is facing the wrong way or is too far out of range. It can cause runaways when spammed due to the way click to move works. /assist + /startattack is usually enough to get the slaves on the right target when they are already in range.