If I understand this correctly, it will only address correcting a number in the calculations; it will not address a situation (such as mine) in which the fundamental problem is that CRA does not have the RL-1 document itself and requires it as documentary evidence. Apparently (and much to my surprise), CRA never receives nor stores the RL-1 documents; they simply trust the individual reporting, unless they decide to do a reassessment. I believe the only way to get the document to CRA is by mail to the appropriate tax office.
