Zavage hits like a girl, though. The main thing on his zeta, AFAIC, is the cleanse. I dunno who you have on your roster, but here are some tips:
If you happen to rely on debuffs, hitting savage will speed up his turn and cleanse the other guys faster. So whenever you have no good debuffs on the other toons, take some time to chip away at his protection with your non-important attacks.
Then after he takes his turn, if stealth/evasion gods allow it, turn your attention back to the other sith and spread out the debuffs while u can.
After you kill one or two sith and savage has eaten the debuffs, turn your attention back to savage and blow him up with boba or annihilate him or multiassist him into submission with GK.
If you don't use debuffs, just leave him for last... gods of stealth/evasion willing. Then use your dps/annilate on him.
If you don't have at least 6 or 7 of the following toons: baze or boba or gk or chirrut or rex or dn or zylo or TFP or Rex or full sith squad etc... well, heck. Welcome to the new meta.