True on all points. I also thought that they, theoretically if they are alive still, could be at some more distant refugee camp and Lona just never found them - with the chaos, separation and death during the Sybaris fall in mind - Lona just does not have any reasonable basis to think that they are still alive.
At the end of day it all depends on Eccma and what he choose to do with it.
As a little sidenote: sure, if they were to be still alive they most likely would be in dire living situation. But at that point, at least on my playthrough, Lona is basically a killing machine which can go head-to-head with any enemy and has more than enough money to spare to, theoretically, take care of her family (i.e. put them on the ship).