I've posted about this before - but I think the HM's were around before the takeover. In TT (I get it, it's just a book) but it seems like overnight every 'powerful' woman was rounded up and put into a stadium and executed (and when they got there it had already been going on? Like how did they not notice lol).

But I think there were 'voluntary participants' pre-takeover. In the June/Luke escape scene they show reflections of what look like a wife/HM walking down the street when they're in the car. There's also a line when June arrives at the red center where she says "we only saw glimpses of them in real life/we didn't think it would last". I try to think of the takeover in geographic terms.