I got an update from Pearson on Jan-15:
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Thank you for contacting Pearson VUE GMAT Customer Service with your concern. We have researched your request and would like to let you know that there were no errors found when we reviewed your exam. All items on the exam were presented and responded to. No items were skipped.
Each exam goes through a two-step scoring process using different algorithms and is scored at different locations. In order for a score to become reportable, all of these methods must match 100%. The scores that you received on both your unofficial and official score reports are accurate and contain no errors.
Please contact us at your earliest convenience if you have any other questions at 1-800-717-4628 Monday through Friday, from 7 am - 7 pm CST. Please reference case number ###; the case is our way of tracking this situation. We will be closing this incident at this time.
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In any case, I don't have sufficient time left to re-write the GMAT exam and so I am not pursuing this further. Thanks everyone for your help!