Color splotch fixable without frogging?

I’ve been working on one of my Christmas projects–a triangular garter stitch shawl (k5, YO, K to end) for my girlfriend–which is in a variegated yarn, and just today I noticed that there is one place with an unsightly spotch in the lightest color (it’s in an area between where I was knitting with two balls to avoid just such a dilemma. Boo.) I’m peeved that it pooled when I wasn’t watching. The colorway is this sort of ocean blue mix–see here: http://handpaintedyarn.com/images/hh_ibiza1.jpg

I didn’t notice it until today, so there’s maybe two inches of knitting above that point. The yarn I’m using will frog, but it’s a right bitch (sticks to itself), and it would also be a pain because of the two-ball factor. Also, because I’ve been so good about two-ball knitting and because the other colors are darker blue compared to nearly white, it really shows.

My question is this: is there a way to use a crochet hook or darning needle to somehow run a bit of the other colors through or over the splotch, just to break it up? Even for just a few of the stitches? Said splotch is approximately four rows high in garter stitch (maybe an inch X 1.5 inches), but I think it wouldn’t take much other color to blend it back in. Would that even work? Or do I just give it a miss; trust that the person I am making it for loves me and won’t care?

I found tutorials for duplicate stitch, but that looks like it only works for stockinette. I am also concerned about whether dup. stitch would mess with the finished project when blocked. (If it helps: The yarn is bulky weight and I’m knitting the pattern in garter stitch with size 13 28" circular needles.)

I will frog if I have to, but any assistance you could offer would be much appreciated.

This may be a bit drastic, but here is a guide on repairs, which shows how to fix holes. If you wanted to, you could take out the offending part and replace it using this method. The examples are all shown in stockinette stitch, but here is a guide that shows how to graft garter stitch. To break up pooling, maybe changing a little bit of one row would be sufficient, I don’t know. Personally, I don’t think your friend will mind. If it took you a while to notice it, maybe it really isn’t that noticeable, you know?