I have this mod that triggers radiant quests when you talk to a carriage driver. Only a sizable minority of my users are reporting that the dialogue never appears.

The condition on the topic in question is simple: quest stage == 30 (confirmed to be the case) and subject in the CarriageSystemFaction.

Now a lot of people reported this not to be working. Some got it working after adding the carriage system faction to the drivers since it was absent. I'm reasonably sure it's a vanilla keyword added to the drivers by default, so I have no idea where the keywords went to. Maybe a mod had removed them, but we can't work out what might have done that.

Now as I happens, I had a formlist containing all the drivers. So I changed the faction check to IsInList. And it still doesn't work for everyone. I got a couple of folks to check the drivers were the same actor.

Then I have one fellow who gets the "no mission available" quest kicking off. Which means that the story manager got the right keyword, was ignored by three quests whose only condition was that keyword, and then dropped into the next branch where it got eaten by a quest with identical conditioning. (It's a separate branch so I can randomise the non-default ones).

Anyone got any ideas?