Hey folderp—
I don't have very much experience folding scales but I can offer some advice from what experience I do have. I believe (I'm not positive about this) that you should be able to unpleat a section below the scales as long as, when completely flattened, the unpleated paper is only as wide as the section of scales. Here is a *somewhat* related example that I'm partially basing this statement on. For a new project I'm working on, I have a section where scales (I call them scales, it's just an extremely simple hexagon tesselation) transitions to simple horizontal pleats. Here's an image of the front and the back:
 
Of course, it's a different situation, but you can see that through a somewhat messy but symmetrical process, I was able to flatten the transition. This is a transition between two very different patterns, but I believe it works because they are the same width. 
So, what you could *possibly* do is create a somewhat large pleat (horizontally from the angle you took the picture) and try spreading the pleats and collapsing similarly to how I did. I don't think this will immediately work, but I think that if you play around with stuff like that you might ultimately find success.