It was crystal clear that Gulliver doesn't care about Prudencia at all. All he wanted from this was money.
Once he becomes Duke and Odette dies, Gulliver would still be a duke even if he returns to his fief.
He could just pretend to lament what happened to Prudencia and lay low for a few years while secretly enjoying his life.
And in a few years, he could pretend to rise anew and build his former marquessate as his new dukedom and make it powerful with the money he got from Prudencia.
'Truly despicable! He has to be stopped before his plans come to fruition.'
"Shall we speak with Count Rowell too once the collectors leave? Wouldn't he be a valuable witness?" Arabella suggested since she wanted to hear the Count's thoughts.
Alwin and Raymond were unsure whether they should allow her to be exposed to more of the people but she already spoke with Marie so they would be scolded by Ferdinand anyway.