-chucks... Grannh and Yerman your way? For the plotty thing?-
None of my trolls are seadwellers, and as such none would ever be underwater! So all of these are predicated on Grannh reaching at least the surface.
Taz spends considerable time on the ocean (though not really under it), doesn’t like seadwellers, and would be very inclined to get shirty with Grannh if he showed up to investigate her boat. If you’re looking for a bad-tempered conflict, this would... certainly be that.
Widsth is fascinated by all things undersea, and meeting a deepseadweller would certainly get him fanboying and asking nosy questions. His flirtatious, outgoing personality looks like it would mesh well with Grannh’s as well!
Videle doesn’t overtly seek out seadwellers, especially not adult ones (they make her nervous), but she has never yet refused someone medical treatment! So if Grannh ever gets himself injured through accident or fighting, she might end up crossing paths with him.
Videle frequently wanders around the less-habitated parts of the Winterlands, and helps out lost travelers if they’ll let her. She also tries her hardest to befriend introverted people so she can “collect” them, and would probably like Yerman because he’s relatively nice and draws nice-looking maps -- though she might get into a snit if he mentions ghosts, since she thinks those are made up. The healing thing from Grannh’s prompt could work here too.
Widsth is (almost) a blueblood too, and he also likes exploring! Maybe he tries to buy a map from Yerman, or they run into each other in some out-of-the-way place that they’re both exploring. Unfortunately, he’d probably harass the living daylights out of Yerman in search of stories about places he’s been and thou hast truly seen a ghost?!?! Lucky!!! and so on.
Taz is always looking for maps to buy, and also takes pity on people who are obviously lost. But her shady dealings make it more likely that Yerman would accidentally stumble across one of her operations, and get hastily escorted out of the way. OR maybe he tries to get onto a certain mysterious island to map it, and finds it somehow impossible to get to, and later Taz shows up to yell at him for trespassing?? (Taz is forever grumpy, I’m so sorry)