After the final section of the Quest: Don't Lose your Mind, after you decide what to do with Delamain's AI, if you die before getting into Del Jr.'s cab (I hopped onto an electrified pipe or something near the wall), when you reload, you will no longer before able to complete the quest - the side door will be locked, there is no longer a quest marker to Del Jr.'s cab, and you'll be stuck inside with no dialogue. The only option is to load an earlier save.