GK (lead), zBariss, zR2 (number crunch) how do you beat it

If you have a resistance team, use poe's taunt while targeting GK so he can't taunt, then very slowly take down barriss, who will get crit immunity. If you do it right no one will take a turn. If barriss doesn't get exposed, hut another exposed enemy just to get the TM, but concentrate on barriss all you can. After she's dead, game's over