It is difficult to visualize how there could have been much going on without the women lying down on the bathroom floor. This appears to me to be extremely unlikely given the filthy nature of most men's bathroom (and women have informed me that women's are not much better in that regard.) Now a man and woman would be very easy to accomplish sex acts even if they cannot lie down.
Maybe I just do not have a suitably active imagination or this bathroom is unlike any I have seen in bars.
Lesbian (oral) sex lends itself quite well to standing in stalls. That help?