Any re-dyeing would simply apply one color shade to the entire garment. Probably in a shade of flat green and gray or charcoal gray.
Which is exactly what camo-restore does. Do not waste your money on it. Go to a fabric store and just buy 'fabric dye" at a heck of alot cheaper price and get the same result.
What's wrong with rejuvenating faded camo the old fashioned way... with magic markers.
And here I thought that I was the only one that did such things. I spent a week or better coloring in an old Realtree All-Purpose Brown outfit a few years ago. Still looks great today though I don't wear it much.