I am still working through the idea, I have a few ideas.
Men still keep some of their Seeker traditions, and all the Seeker females gain the benefit of Keeper Matriarchy.
The Hyur basically latched on because it was 'fashionable' and useful.
- Its Keeper Matriarchy at its heart.
- But Males are able to challenge each other for acess to potentially offer themselves to females. So still with in the Matriarchal theme of Keepers. Essentially any  females may choose any male and there by pass over a challenge, but amoungst themselves the boys get to challenge each other.
- The hyur are basically just living in the community, they're aware of this sort of tension, and even some Hyur have hooked up with Miquo'te, (perhaps its fashionable to the the lover of a Miquo'te.
Men still keep some of their Seeker traditions, and all the Seeker females gain the benefit of Keeper Matriarchy.
The Hyur basically latched on because it was 'fashionable' and useful.