Quest not advancing

hi,

somehow, the quest line seems to be stuck.

it worked until I got to the mansion the third time. i did not kill xavier, but the cousins got banished. after that, there was one more dialogue in which sebastian said something like "they know what we know" and that maybe the other luxleys might do something about the curse.

but since then, there has be no further progress. is this the end of the quest line? or am I missing a special trigger that is needed in order to continue? i tried advancing the game time, resting and the usual stuff.

thanks,
max