Well I dualled from a swashbuckler to a mage, and I got the thieves guild, but I think it might depend on whether the class you dualled from is active when you would be offered the stronghold.
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Goddess of Undress
Co-owner of the Evil Petting Zoo and Sorceress of the HADB
OLD COOTS eye candy and Disrobed Division of the ORT
And her sidekick Pink
"High hopes...an endless river...forever and ever"