“Locate a Defense Net terminal and search for Cabal intel on Oryx and the Dreadnaught.”
Head into the second room and turn left. Go straight down the corridor and follow it through. Head up the next ramp you find on the left. Take it all the way up to the large room inside the Dantalion Exodus VI. Head over to the left and stay on the upper level. There are some Legionaries waiting around the next corner.
Ignore them for a moment and head farther down this side. You will find a holographic display on the left wall that you can scan to learn something more about the location. Turn around after you scan the terminal. There is likely a pair of Phalanx advancing on you. Deal with them then continue to the left. There are more Legionaries just past the next wall so be ready.
Continue to the left. You will find a number of Cabal below you. Just use the height advantage and clear them out. Go forward and drop down into the lower area of this part of the ship.
Turn to the left. You will find a pair of Psions attacking. Quickly deal with them. You can scan the turbine down near where they appeared. Ghost will report that the ship apparently still has the power to take off. Head past it and up the ramp on the right. This leads you directly to a terminal that Ghost can use to access the Defense Net.
Head for the central display in this area. You will see a holographic projection of the Dreadnaught there. Go over to it and have Ghost scan it. he will get the information you need.