There are many examples of Houses that should have died out by CK2 standards but didn't, and with very large rulers, a lot of my examples may come from Colonial Europe, but for Example Maria Theresa Von Habsburg, had many Children from her Husband Francis I von Lorraine -- they formed the Habsburg-Lorraine Dynasty -- while you might say it's not exactly a 'matrilineal marriage,' it is very similar. If these kinds of marriages didn't exist -- the Habsburgs would have dissapeared from history, but they didn't. So it may be more accurate that families that had 'a lot of renown' combined with other families to make Cadet Branches of the same house, but this still allowed the Children of Maria Theresa to inherit Austria, and still be high on the succession list for countries/states run by the Hapsburgs, Lothringen, and Habspburg-Lothringen's -- but we don't have this as a game mechanic. Same happened with Elizabeth of Russia -- so I might venture to say matrilineal marriages didn't exist -- but 'joint marriages' existed where two houses merged into one, but this can't exactly be simulated by the current system.