So I at least somewhat made a discovery a few minutes ago. The daily marriage quests do seem to work.
I spawned the Matchmaker Servant in my world NPCGEN and attempted to take the 'daily marriage quest' by two that were not married. The quest cannot be taken by two ppl that are not married (success so far:) I attempted this with two male, two female, and a male and female char.
It also appears that you (correctly) cannot take this quest with 3 characters in a squad.
It will issue the quest to two married persons though with success. Now obviously I couldn't actually do the quest to test the quest reward (to complete a 'daily marriage quest' I have to add in more NPCs and mobs and whatnot, for those who haven't done one or don't know what they are), but so far it does appear to be correctly working :D
Like I stated, this is a rather recent development so I haven't been able to analyze anything too in depth, but I will surely keep posted on any further findings of mine.
A quick glance at tasks.data points out these first obvious differences (that appear to be the same across all daily marriage quests, highlighted in yellow) that may control the fact that you have to be married to the person you do the quest with:
well, like I said it appears to be working so far. I am currently going to have to add corresponding NPCs and MOBs to fully test through the quest reward...
1. Checks if 2 and not more ppls are in party
2. Checks if 1 is male and 1 is female
3. Checks if male char has completed the male marriage quest
4. Checks if female char has completed the female marriage quest
5. If everything is ok the party can take the quest
you *have* to be married, and that part works just fine. It will not issue the quest to two characters that are not married, just as mentioned above. I am only not sure it works 100% because I have not completed adding NPCs / MOBs to actually complete a quest to make sure it properly rewards the players. (That and I bounce all around; right now I am actually working on a35)
I can now confirm this as working, so far I have added all daily marriage quest NPCs and MOBs to my world NPCGEN. I have also been able to fully test 2 of the 7 actual quests to assure they work all the way from quest retrieval through quest reward (your exp/sp,sweet memory, and Sincerity Pack). The two that I can fully confirm as working are "Sad Lonely Widow" and "White Saintess"