It's possible that the assembler thought the 5th element was symmetric and put half of them in the wrong way. You don't say that you are sure the lens is in backwards. I think you can be. The difference between 150mm and 200mm radius may even be visible to the eye with a straightedge. The focal length is half the radius of curvature.
Plain glass make a good mirror.
1 and 2 are crude but all you need to know is which side of the lens has the deeper hole ground into it. If the deep side points to the CCD you've found an error. It has been great having him work with me on finding a fix. It looks very promising that this will be the fix that we need.