Hair highlighting goof

There's no need to shave it off for this, (unless you want to be bald).  Did you use the same kit you always used before?  There's no reason it shouldn't give you matching results unless you did something different (left it on for less time or something).  You should get matching results if you try to do all the orange hairs again with the same kit you usually use...do test ones first to make sure you get the timing right and get something that matches.  You will probably need a friend to help you with this, so they can see what they're doing and get the stuff only on the highlighted parts that are orange (you won't want to redo the part that wasn't your roots).