I don't know why someone else thinks there might be another gene in there unless they are just use to seeing bad quality pastels, which the market is flooded with these days. That snake is just a pastel. Not the best pastel, but not a bad quality either. It's above average I'd say. It's young and it already has a very prominent brown-out line which means it will get darker. It does have some very nice blushing though. Just not yellow enough. It's mostly orange colored which is what gets darker with pastels.
There are different lines of pastels. Some have that type of pattern which is more blushed. Some have a solid black pattern with a more yellow body coloration like the true NERD lemon pastels. They all look different and the looks can be changed, improved, or worsened by selective breeding.