well the paleologos of Montferrat were extinct know in the 16th century. I think your best bet is for Frederigo to not die and lets say the Italian wars go much better for France as a result of which the pro french policy of William IX and Anne De Alencon who would be regent pays off, by which I mean the spanish are booted from Northern Italy by the French. In such a case given their involvement the Marquise of Montferrat is bound to get rewarded and though it remained an imperial fief with a much stronger france I think montferrat could survive. let us say Boniface gets lucky with his marriage or turns out to be a capable ruler who is able to push back the dukes of Savoy and this could lead to a resurgent montferrat which under right circumstances could play a role as a strong player in northern Italy albeit as a french Vassal. Then somehow prevent butterflies which is unlikely but lets say not much else changes in Northern Italy and Montfferrat somehow takes the place of OTL Savoy (Big call here). In such a case following a policy and luck similiar to savoy not too much should change then during the revolutionary period let us say Montfferrat which by this point may have close ties to the french royal family serves as a bastion for the fleeing old regime nobles and also perhaps as a haven for Louis XIV who manages to successfully escape from Paris. What would follow would be a capable ruler of Montferrat who with Austrian helps manages to win the support of Toloun and regroup with the rural peasants and royalist forces and successfully defeat the revolutionary French army. Let us say by this point due to the rise of Montferrat somehow they manage to marry into the Bourbon royal family or perhaps being a powerful state in Northern Italy the daughter of the ruler of Montferrat marries Louis XVI son. In such a case what we get is restoration and eventually Louis XVII who is married to the paleologian marquess as King of France. Albeit not having Napoleons borders let us say as a result of marriage the powerful Northern Italian state of Montferrat gets inherited by Louis XVII, perhaps the Marquise of Montferrat dies shortly after restoring the royal regime and dying as a hero of France who protected the old order would fulfill the POD I think. But honestly I dont see a family like Oriundi pulling a Napoleon.
