Did any employees survive the incident?
A few doctors were shown escaping through the reception in the level Hospital, and a guard can be seen strangling a patient to death before hiding in the latter's cell. A guard and a doctor can also be heard discussing ways of dealing with the situation. One more guard can be seen hiding in a security room, having barricaded himself in.
There were a couple of guards in the level Prison who mistake Waylon for a patient and block him in before running out into the courtyard. In that same level, a guard can be seen locking the door for a decontamination gate control room while Waylon is pursued by Chris Walker. Another guard can be seen hiding in a prison cell.
In the Prison Block level, two guards can be seen alive, although they die the moment Miles sees them.
Another employee can be seen tied to a chair in the Male Ward before Miles encounters Trager.
Lastly, a character named Cooper can be heard conversing with someone else behind a locked gate in the level Hospital.
Cooper: "I made it. I think it's safe. Can you climb up?"
Other person: "I'm coming, Cooper! I just have to lock the... there. I'm coming! Hold on."