I know this sounds a bit vague, but, I want to avoid spoilers for others.

I’m in the last hallucination of “The Shadow”. I’m sent to the floating square where I kill a few baddies. I’ve killed a few but no more spawn. There’s lightning going on, a giant shadow dude/ dudette, and nothing happens. I think I’m supposed to be taken back to Vault 9 but I’m stuck there.

I went back and made the other choice just before the floating square and I’m sent back to the vault. But, that’s definitely not the choice I want to make.

ETA I’ve gotten all my head bits and gotten fixed up by the doctor, walked the catwalk into the fake vault, shot the Roman, got onto the floating square, killed another Roman and 7 shadow people. The giant shadow person in the background disappeared and one appeared to the right. That’s where I am now. I left the game on for a while and came back to the same spot.