It's interesting with a marriage error like this. Assuming this marriage was in England and Wales, and that you are referring to an image of the register rather than a certificate, was the correction made at the time or later? If it was made at the time, then the error might have been in both copies of the marriage register or just the one. As I understand it, if an error is made in one copy of the register but not in the other, then the quarterly returns to the registrar can be made from the uncorrected version, so a certificate from the GRO wouldn't show the correction. However, depending on which register was later deposited with the registrar, then a locally produced certificate might or might not show the correction.