I am inclined to think that is not cell rot, but I could be wrong. I don't think I've ever seen cell rot on scales like that. Also, it looks like there is crud inside the scales, and I would guess that is what caused it. But, take a look inside the scales and see what you can see. If there is stuff caked in there, I'd say that's probably what caused it. If there is discoloration that matches the marks on the blade, then it probably is cell rot. Either way, you'll probably want to keep the blade open and store the razor away from the rest of your razors.