This seems to be a common thing to happen for those that have taken remote invigilation. Have you emailed ACCA on this ? Or Have you received any further news from ACCA?
As far as I know, when at initial marking student fails. The answer script will then be passed on to few(around 3) markers and the one with highest mark is chosen (eg 49%).
The closest you are looking for is administrative review however that is NOT a remarking service as stated on ACCA website, it merely shows if you pass/fail for each question.