The mission this cut scene is from is the first in Forsaken. Cayde, Petra and us go to the Prison to investigate the Outbreak. During this [spoiler]We mess up, causing the incident that leads to that cutscene[/spoiler] Resulting fall cuts out comms and you know the rest. People played the mission at E3. Oh and the spoiler tag kinda is one so don't click if you don't want to know more. The info in it is already out there but just wanna preface it.