The first image is what seems to be loaded when the CR2’s are converted.
Which looks OK, there are grey scales etc. I’ve tried every kind of raw debayer interpolations and they all look broadly the same, I assume that there are some pixel level differences somewhere but these are not causing the issue.
I can’t seem to recreate it right now (I have rebooted), but instead of greyscales as the above image, all I would get is 100% black or 100% white. Will try again to recreate tonight.