I made pasta dough (flour and egg only) and still have half the dough in the fridge. It is folded in thirds and in plastic wrap, not yet rolled. After a day or two it started turning darker which I didn't expect. I'm wondering what I can expect if I roll and cook this pasta in terms of taste, texture and appearance. (I'm not asking about food safety.)
I don't have the exact same experience, but I did have some egg pasta noodles I'd already rolled out in the fridge for a couple days, and they discolored like yours did. I cooked them anyway and really didn't detect any difference. I felt, if anything, the pasta might have been a bit firmer than if I'd cooked it fresh, but I'd think that has more to do with partial drying or gluten formation/relaxation in the fridge than anything. I didn't taste any difference through the sauce, or notice a change in appearance.
That said if you only roll it now, I don't know if you'd have the same, slight textural difference I did.
....You could perform a simple experiment, pinch some off, roll it into a sheet, cook and see what you think. Since my pasta, eggy though it was, might have had more salt (or something), there's no guarantee my experience would be the same as yours.