Unfortunately the batch, in my opinion, should be discarded. Carmoisine is related to intolerance issues in high amounts in adults and maybe hyper-reaction if consumed by children. If I recall correctly in Europe the max amount allowed in non-alcoholic beverages is 50mg/l.
To my knowledge there is no chemical that can neutralize carmoisine (at least a food safe one) and also if you dilute it too much the quality of your product will take a severe hit.
Although it involves an economic loss, I think it is better in the long run than a bad reputation due to bad safety/quality reasons.
PS: I do have to mention that there may be a way with oxidation but it's propably not worth the effort and the end result might still be something at least of poor quality.