I emailed Kevin Winter with some questions and I got this reply:

"The parents are a normal and a black pastel. I think Gary Liesen still has them but I do not have any pics. It is possible that the first mutation started in these snakes.

It appears that the codom gene for trick makes yellow just like the codom gene for yellow belly makes ivory. As we know, many codoms make variations of white snakes which still blows my mind. I am sooo glad that a super trick is not a white snake.

I am betting that the yellow in the super trick is xanthism. My trick lesser has much more yellow than a lesser and I bet a super trick lesser wil be a very yellow animal."