I also encountered the issue on PC, the red pool doesn't appear. I bought the game last week, so well past the difficulty patch. I can provide a save if one is still needed. The game is amazing but this bug is infuriating.
Update: I saw in another reply that standing still near the gate for several minutes could solve the issue. IIt worked for me. I stood there for maybe 5 minutes before the red pool appeared and I was able to proceed in the game.