That "Morpheus send me with message for Master" dialog line would work if you were wearing a purple robe (for example from Jane in Hub), but it's death sentance unless you know how to talk master down. But you will still need to get back up and I'm not sure if it will work that way. So it's probably better to clear the passage on the way down. Mechanical lockpikc not work on electronic door. You need Electronic lockpick or just a skill. Elevator there leads into tiny 4th floor with 2 supermutants and a nuclear bomb. You can initiate that bomb as alternative ending. In some versions it require special key from Lieutenant.

Thanks for the upload... love this game... prefer Fallout 2 which i'm currently playing for the hundredth and something time haha