Isolate General Kenobi; fracture Jedi Knight Luke; spread shock so Palpatine gains huge turn meter from his basic and lands the stuns; and maintain ability block with Vader. Focus most damage onto JKL, so you don’t kill off the other Jedi too early.
Apart from Vader (as he goes first), gear level shouldn’t matter too much, as you maintain so much control, the enemy shouldn’t have many opportunities to hit you. Finally, load up Palp with your fastest mod set. High speed with a lot of shocks on the enemy, and passive cleansing from Barris, can result in back-to-back turns.
Be aware, General Skywalker cleanses when critically hit.