February for the USS Vigilant

Having laid over at Deep Space 6 for repair and resupply, the USS Vigilant has now taken the first steps on her journey into the Zeta Gelis region.
Answering a distress call from Zalkonian Space Station Ea-435, the Vigilant crew have found evidence of an as yet unexplained atrocity: every member of the station’s crew compliment has been killed dute to the widespread release of a concentrated biotoxin, save for two men, located in the station’s command centre. While the finger of suspicion would seem to point directly at the survivors, their claims to have lost their memory have been corroborated by Lieutenant Ilyazi Malon’s Rodulan telepathy.
Detailed scans of the biotoxin from the ship’s astrometrics lab have revealed that it was created synthetically. The implications of such a discovery are truly worrying, as is the concentration of the toxin within the station. Teams from the Vigilant have beamed aboard to attempt to piece together the mystery of what happened aboard station Ea-435 and determine the reasons behind the biotoxin’s creation.
So far, every question seems to have led to another question. Who are the mysterious survivors? What secrets does the space station hold? And why haven’t the Zalkonians answered their own distress call?