I actually completed it without the use of pillars as a Medic-specced Operative...just kited and used ranged attacks. I'd stun him and heal up every so often, but as long as you stay on the run you'll outlast him. My companion died pretty early on due to his AoE attack, but I managed decently on my own. Granted, I think LoS'ing with the pillars will save you some grief if you don't have many heals, but this quest is do-able solo.