Thanks for your help - really appreciated!
The cutscene doesn't occur now, so at least I can get on with the game. If the quest has hit a dead end, I'll just DL ver 8 and make Angelo tag along in my next playthrough.
You're probably aware that I killed Sawara already yes? Back in chapter 3. After that I was approached by some guy who wanted the katana. I refused and he left. I still have the katana in my Bag of Holding.
Global("AdAngelTeleportedTo","Global") is set to 1