That is interesting Cross,
It may very well be as you say. It makes more sense that way. Giving up the natural way to have sex for an unatural way. Rather than regular, they dipped into anal. And there is no reference to the sex of the persons they committed the acts with as with the men. And the likewise would denote that the men did the same as the woman did.
Since two women cannot penetrate each other, it is reasonable to suggests that it could be male and female...