Stuck at a mission :(

[code99]

Hello, this is driving me crazy, im at the mission where heretic offers to go to alien systems for artifacts and all that , so we meet in system x220 or something and we do what we went there to do ... anyways, after returning from that mission, the last objective sais "Escort Heretic to inhabited systems", well thats fine by me , we set our course and fly until a pretty large group of ships ambush us and heretic dies ... no mather what i do they kill him and sais "game over"... i tried everything that i could think of but still nothing, he keeps dyeing. I tried different weapon loadouts and different aproaches but they still get heretic ....

Am i missing something ? How did u guys pass this mission ?
thanks