Unable to exit building after quest completion ("An Instrument to Unfold Space & Time")

[quondoronda]

Near the end of the quest "An Instrument to Unfold Space & Time" it is possible to get trapped inside the building without any way to leave, effectively breaking the game.

This happens when near the end of the quest you (sneak) attack Vaillencourt and kill him instead of talking to him and initiating combat via dialogue. His forces will still atack you but even after killing them all, the map will still show "Deal with Vaillantcourt's Forces". You can go back to the scientist and get the quest reward from her but the door in the hangar that should allow you to leave the facility will remain closed.

I've tried this mulitple times and the bug happened at every single attempt.