It's definitely possible that you haven't seen anything. He might be a shy breeder, but it's also possible they aren't breeding. Have you bred either one of them with different snakes? If you don't want to breed her with anything else, just keep pairing those two and hope you just haven't caught them in the act.
I have not bred either previously. I did insert my male Super Pastel with the pair last night in hopes to spur the Double Het. I'm hoping your right, and have just not witnessed anything yet, but I'm pretty observant. thx