No one, obviously, is about to give away Dublin to Mollys.
Neither Bretonia, nor Gallia.
The question is: why Mollys exist for so long inside of the Bretonian house (actually, why criminal organizations are not being elimimated by houses with time?), and how long will it exist when / if Gallia conquers Bretonia?
What does it take for a house such as Gallia to eliminate, well, a criminal population such as Mollys? But again even Gallia has thriving outlaws inside of its borders...
This brings up a conclusion, that if no house is able to completely eliminate criminal groups, then those groups can simply go on their own and ignore the outer conflicts that affect "their" house. Thus, Mollys have no real reason to fight neither Gallians nor Bretonians. But this means that they will not be able to hold and control vast territories.