Even though they are distinct in their cultures and appearances, I think the two tribes are similar enough that we can assume Keepers of the Moon also have only a few breeding males.

That being said, the added respect for the mother might imply that the breeding male chooses a lasting partner, rather than sticking to one-night stands. This female would be revered as queen of her tribe for a long time.

The Pern series of books has a similar scenario, but with opposite genders. The senior Queen dragon (there can be multiple gold dragons, but the eldest is Senior Queen) will have somewhat regular mating flights, and the one male dragon that catches and mates with her more-or-less becomes their leader until the next mating flight. Like the Miqo'te, this ensures that all of the Queen's children have the genes of the strongest male.