I had problems with him and discussed with a friend who had quite an easy time defeating him. I proceeded to reset the quest, which forced me to go back to my ship to use the holoterminal but returning to fight the Lieutenant I managed to defeat him rather soundly with Kira before switching back to T7. So I'd try to reset the quest and see that works for anyone still have problems. I've had difficulties a few times and so far resetting has always worked for fixing problems. Hope this helps.