Actually, I had a similar situation in which all the Mountainhomes had been wiped out in worldgen, but somehow the king had survived. In my case, I received migrants, nobles, king, and caravans (but no dwarf liaison) and built up a fortress of over 200 strong on the glacier.
The more interesting things happened after abandoning that fortress. Since there were no Mountainhomes, I couldn't embark as a dwarf adventurer, so I hit "play now" as a human. It took around ten minutes to load that first adventurer, and it turned out it was because the fortress was descending into chaos! All the snow that had perpetually blanketed the glacier and tundra miraculously melted, flooding the land in 1/7; huge sections of surface and subsurface glacier liquified, caving in tunnels and leaving a once level surface as jagged and unnegotiable; and many of the captives of the former fortress ran free to cause mischief, with naked elves babbling on the permafrost and a pissed off dragon and a goblin-raised human pikemaster slaying one another in the former zoo! That first adventurer met her end while ascending out of the forge with liberated arms, clothing, and armor when an entire wall of ice decided to melt and refreeze with her in it.
When I finally got around to exploring the world map, I discovered another thing. I originally settled on a glacier surrounded by forests, hills, and plains with orcish towers to the north and east, interspersed with the blasted ruins of some failed human civilization. What I discovered instead were what looked to be human cities of varying populations, the largest at capitol size. As I approached one of the smaller towns, all I saw were ruined houses. Deeper into that waste, I began running into human and dwarvish merchants. Did they make a merchant camp? I set out for the capitol, and there amongst the shattered buildings were dwarves! My dwarves! Warriors and workers and king, all together, reviving an ancient civilization! Well, maybe not that since every dwarf claimed that he wasn't home yet and none of the buildings were rebuilt, but it did have the stark atmosphere of a refugee camp - dwarfmen and dwarfmaids with no place to go, trying to make the best of the situation.
It made me wish that I could resume the worldgen to see if they could accomplish anything there.