Well you should be able to play dwarves in that civilization, Can you upload the save to the mantis bug tracker? It sounds like the save is bugged.
Too many problems with it, world genned in 47.03, messed with scripts while playing around artifact recovery, even though I was VERY careful not to save afterwards there's a good chance it's messed due to 3rd party stuff. Doubt there's useful information for Toady there. Tried recreating the world from export image in the new version ( 60 years down the drain, was testing if I could domesticate animals for civilization, Expert giant vulture tamers on one fort... soo many scattered caravans). There was also the time when my winding path for the depot was cool but started causing dwarven caravan colliding with human caravans.
On a side note, when I recreated the world in the new version just now, if I wait until my original worldgen date, mountainhome gets taken over by goblins so there might be another issue. Although, I can create adventurers from the nation if they survive. Never got barons or hillocks on that save in any fort despite fortress wealth and success. A retired fort gets a baron, immediately moves to original mountainhome, same with queen, soon as I retire, queen packs up and goes back to the original fort.
I checked the recreated world if I gen 5 years less, mountainhome survives. I won't mind even if it gets taken over to be honest. Plan is to do adventurer/fort sessions to build up a mere 1 fort civilization.
Saved it aside in case I'm interested in playing from that existing save. There's weird and !!fun!! stuff there. Mayor of mountainhomes is a necromancer, along with captain of the guard. Both are notorious serial daters and they had a brief affair. They even act like a villianous entity, going around stealing crap and plotting. Also, forgot to butcher the caged dragon in one fort before retiring, half the fortress melts when I try to unretire that fort. There is a dark goblin pit nearby, when raided and prisoners released, results in 200 merchant visitors who don't seem to want to leave.