Let's do an experiment...
What if one found a "sex worker" who, after a nice make-up-wardrobe-coaching revamping could stand in as a (hopefully) convincing Tiffany double & have her meet with these two individuals separately? Just in a couple hours, she could have a "meaningful" conversation with them about their lives, making them feel as if the moment they've been waiting for has arrived but at the same time easing them into getting the notion that she operates in a whole other level & it's just not possible to spend her whole existence with them. However, as a single "act of communion" that shall last the rest of their lives & give them the power to change it in the best possible, positive way, she will be intimate with them. So she proceeds to "do it" with them (using safe measures, of course or maybe even contriving & simulating the actual physical act).
This would be done with security & proper (hidden) observation, of course.
You never know if, for example, in the case of the alleged "intersexual" individual, the actual contact with another woman might end up repelling her. Same with the other guy. Maybe once they both think they get "lucky", the illusion (delusion?) will be shattered for good...hopefully in a good way.
End of the session.
;)