The quote allowed me to jump to the text. I found that the only check is this:
(troop_slot_eq, "$g_talk_troop", "slot_troop_does_not_give_quest", 0).
I checked the code from a year ago and it was set to 1 back then.
I don't recall messing with it, but there are several people who work on the mod.
I returned the slot to the default of 1.
The lord dialog is very revealing. It appears to be fixable but not today.
It will still be another week before I can find time for the patch.
PM me if it's urgent and I'll post a hotfix via dropbox.