... now I can't talk to any NPC, in fact.
Tried to reload the save several times, didn't help.
This is basically the same issue I have. Do a crime (steal from someone that can see you) and the dialogs will reappear.
The only issue is (I have yet to confirm) that you cannot travel to ZixZax after that, a message appears that one of my main characters needs to finish a dialog even if no dialog is ongoing
Cheers,