Other Adventurers

[Enkidoh]

Ok so we know that other players can be our character's adventure friends and that's who npcs tell us to gather. That's not what I'm confused by and want to know if there is an answer to. Going back to the first three dungeons we see other groups get sent to them when we're in that part of the msq. Now we know the fate of two of those groups and outside of Sastasha there are two more groups that have pre and post dungeon clear text bubbles. We get the credit for all three places, but we also don't see any of the other groups. So how did one group die and Edda's group lose their tank? Did they take a different route or something?
Also is there a reason why we don't see npc adventures anymore?

Avare (Edda's fiance) died because he was too cocky and pig-headed as a tank (he would rush ahead with early pulls out of range of Edda's Cure spells, and ended up being decapitated by a monster, which the rest of his party just blamed poor Edda the healer for - sound familiar? It's a take-that against players being too sure of themselves and blaming each other when things go pear-shaped).

As for the other two 'npc groups' you met there, one group later perished in Tam-Tara Deepcroft (ironically you can actually encounter them in Palace of the Dead - evidently their souls have not found rest as a result) where as the other, a two-person partnership of two elezen adventurers (an elderly male GLA and his younger female ARC friend), actually end up retiring from adventuring outside Copperbell Mines (unfortunately their names elude me I'm sorry).

Much later they return when they are recruited for the Steps of Faith battle, along with a number of other adventurers (ironically, most of these npcs that appear in the cutscenes after this fight, were originally player characters, they were winners of a competition SE ran a few years ago where your character could be added in a story cutscene as a npc. ), and end up joining the Scions later in Heavensward, where they can be found in the Rising Stones.

Adventurer NPCs do show up throughout the story - the Waking Sands (and later the Rising Stones) are full of them (because the Scions recruited mostly adventurers into their ranks, whether they have the Echo or not - most do not). Also it should go without saying that most of the NPC patrons of the three Adventurer's Guilds are adventurers, naturally.

And a final footnote to Edda and Avare is when you first unlock Sastasha HM, fittingly there is another NPC party there outside the entrance which are basically a pallette swap of Edda's old party, right down to their classes and gear (male highlander hyur GLA in red, rather than blue, armour, female woodwight elezen ARC, female midlander hyur CNJ and plainsfolk lalafell male THM), and they even remark how things seem familar for some reason and that he has a bad feeling about this mission, that he hopes he "doesn't lose his head." Tempting fate me thinks.

So npc adventurers do show up throughout the game, you just have to keep your eyes open and really read the dialogue and take note of your surroundings.