Does the "Taris" mission in Iconia unlock the missions to Gamma Orionis? I was unable to beat the psionic warriors until today and I finished the mission several weeks after trying it for the first time. Admiral T'nae then disappeared from the "Hail Starfleet" area but there were new missions in "Hail Starfleet", to Gamma Orionis.
I almost never got to Gamma Orionis because of those purple outline enemies. I used all Vulcans in my away team to Taris, used focus fire, and used a blast type weapon against the Reman Captain with the psionic powers and then against Taris herself. That is how I finally finished it.