well vulcan would have been along the way.
cardassians were known during the time of enterprise/ a carrdassian poet
was living on vulcan.
it is possible like other ships rajiin was on a ship that got sucked into the expanse when they got to close to the barrier.
i always wondered if some of the odd pockets of space could be retcon into being part of the former expanse.
tng seemed to especially have a lot of them.