I had a group of four make it all the way to the last room. Manus of Borg (Rebecca Simmons) was difficult to access. I have a very hard time jumping around, and with the Tactical Drones constantly respawning, it gets very difficult to lower the shields and upload the virus in time. We did manage to get her on the central platform, but then she just owned us. I recognize that many players have been able to complete the mission, but even on RA, it was hard. I would suggest that once the shiled generator is detroyed, it does not respawn.
My recommendation is that once Manus fights directly, then the force field should drop and players who respawn should be able to get back into the fight immediatly. Not have to go through the trouble of doing the generators again.