I agree with both, dyeing is too 'iffy' and a sharpie is likely your best bet. The reason why? Here is a little fabric chemistry: once you bleach something, its chemical composition changes permanently as such that it will no longer hold dye particles. If it does, it will not have the same intensity as the rest of the fabric and the dye will wash out over a few launderings. So, sharpie it is!
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