"Flight to Salvation" - "The Veil is Torn" [Campaign 4, Mission 2]

Please help me complete the "Escape to Salvation" campaign for Zehir, specifically the "Veil Concealed" chapter. I can't figure out how to get to the left side of the map, both in the underground and on the surface. I've explored everything on the right side... there are no teleports (except for one leading underground to the Asylum) and no passages.