It's weird Brian didn't think, even for a second, the value of the title. A jump from a count to a duke is considerable. It would be worthless for anyone not able to shoulder the debt and not possessing military and economic power fitting for a duke, but if one does possess those qualities, they could be a real duke, not just a paper tiger duke and a laughing stock.
It's more worrisome that the current emperor is still following the already dead, ancient emperor's order to keep house Claudia suffering. Liam might want to find out if marrying Rosetta means becoming the emperor's enemy. On the other hand, if the emperor is his own man at all, he would use the chance to end the whole stupid suppression and be done with it. It hasn't got anything to do with him anymore, not even his father or father's father, I imagine.